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Travel_Word_Problems/269229: A Boat goes upstream 40 miles and downstream 86 miles in 8 Hours. If it goes upstream 24 miles and down the same distance in 5 hrs, what is the boat speed? 1 solutions Answer 197510 by ankor@dixie-net.com(15652)   on 2010-02-14 14:18:20 (Show Source): You can put this solution on YOUR website! A Boat goes upstream 40 miles and downstream 86 miles in 8 Hours. If it goes upstream 24 miles and down the same distance in 5 hrs, what is the boat speed? : Let x = boat speed in still water Let y = speed of the current Then (x+y) = speed downstream (x-y) = speed upstream : Write a time equation for each statement : "A Boat goes upstream 40 miles and downstream 86 miles in 8 Hours." + = 8 Multiply by (x-y)(x+y) to get rid of the denominators : 40(x+y) + 86(x-y) = 8(x+y)(x-y) 40x + 40y + 86x - 86y = 8(x^2 - y^2) 126x - 46y = 8x^2 - 8y^2 Simplify, divide by 2 63x - 23y = 4x^2 - 4y^2 4x^2 - 63x + 23y - 4y^2 = 0 : " If it goes upstream 24 miles and down the same distance in 5 hrs," + = 5 Multiply by (x-y)(x+y) to get rid of the denominators : 24(x+y) + 24(x-y) = 5(x+y)(x-y) 24x + 24y + 24x - 24y = 5(x^2 - y^2) 48x = 5x^2 - 5y^2 5x^2 - 48x - 5y^2 = 0 : Try to eliminate some of this, mult the 1st by 5, the above by 4 20x^2 - 315x + 115y - 20y^2 = 0 20x^2 - 192x + 0y - 20y^2 = 0 -------------------------------------subtraction eliminates x^2 and y^2 -123x + 115y = 0 115y = 123x : I don't think this is possible, the current exceeds the boat speed

Travel_Word_Problems/268803: a boat can travel 42 miles upstream and 42 miles downstream in 10 hours. if the speed of the boat in still water is 10mph, what is the speed of the current. I'm not sure how to re-arrange the formula for these variables, here's what I tried: 42+42/10=8.4 (presumably the average speed) 10mph-8.4mph=1.6(presumably the speed of the current) 1 solutions Answer 197507 by ankor@dixie-net.com(15652)   on 2010-02-14 14:06:50 (Show Source): You can put this solution on YOUR website! a boat can travel 42 miles upstream and 42 miles downstream in 10 hours. if the speed of the boat in still water is 10mph, what is the speed of the current. : Although there is a certain logic in what you are doing, it's not right Here is what they want I think : Let x = rate of the current then (10+x) = speed downstream (10-x) = speed upstream : Write time equation; time = dist/speed : downstr time + upstr time = 10 hrs + = 10 : multiply by (10+x)(10-x) to eliminate the denominators 42(10-x) + 42(10+x) = 10(10+x)(10-x) : 420 - 42x + 420 + 42x = 10(100 - x^2) : 840 = 1000 - 10x^2 : 10x^2 = 1000 - 840 10x^2 = 160 Simplify, divide by 10 x^2 = 16 x = x = 4 mph is the current : : Check solution by finding the time (14 mph down, 6 mph up) 42/14 = 3 42/6 = 7 ---------- total = 10 hrs

Money_Word_Problems/269030: I have $1500 in a savings account drawing 6% interest and would like to make a payment once year for three years to have an ending balance of $10,000 at the end of the three years. I need for these payments to be the same amount to make it easier for me to remember. Can you please help me by giving the formula for this? 1 solutions Answer 197405 by ankor@dixie-net.com(15652)   on 2010-02-13 21:56:06 (Show Source): You can put this solution on YOUR website! I have $1500 in a savings account drawing 6% interest and would like to make a payment once year for three years to have an ending balance of $10,000 at the end of the three years : I used the financial feature on my TI83 with your figures and came up with $2579.93, just make it $2580 deposited every year (compounded once a year) If compounded quarterly you only need 2574

Square-cubic-other-roots/268734: Maximum sail area. According to the new International America’s Cup Class Rules, the maximum sail area in square meters for a yacht in the America’s Cup race is given by the formula S =(13.0368 + 7.84D1/3 - 0.8L)^2 where D is the displacement in cubic meters (m3), and L is the length in meters (m). (www.sailing.com). Find the maximum sail area for a boat that has a displacement of 18.42 m3 and a length of 21.45 m. S (m2) D (m3) L (m) 1 solutions Answer 197401 by ankor@dixie-net.com(15652)   on 2010-02-13 21:40:45 (Show Source): You can put this solution on YOUR website! Maximum sail area. According to the new International America’s Cup Class Rules, the maximum sail area in square meters for a yacht in the America’s Cup race is given by the formula S =(13.0368 + 7.84D1/3 - 0.8L)^2 where D is the displacement in cubic meters (m3), and L is the length in meters (m). (www.sailing.com). Find the maximum sail area for a boat that has a displacement of 18.42 m3 and a length of 21.45 m. S (m2) D (m3) L (m) : The think the formula should be the cube root of the displacement S =(13.0368 + 7.84(D^(1/3)) - 0.8L)^2 : S =(13.0368 + 7.84(18.42^(1/3)) - 0.8(21.45))^2 : S =(13.0368 + 7.84(2.641)) - 17.16)^2 : S =(13.0368 + 20.705 - 17.16)^2 : S = 16.582^2 : S = 274.962 sq/meters of sail

test/268697: Diane canned 18 quarts of peaches, 15 quarts of apricots, and 12 quarts of plums. she would like to place the quarts into the greatest number of boxes so that each box has the same number of each kind of fruit. how many boxes does she need? 1 solutions Answer 197395 by ankor@dixie-net.com(15652)   on 2010-02-13 21:03:47 (Show Source): You can put this solution on YOUR website! Diane canned 18 quarts of peaches, 15 quarts of apricots, and 12 quarts of plums. she would like to place the quarts into the greatest number of boxes so that each box has the same number of each kind of fruit. how many boxes does she need? : I think 3 boxes. 3 is the only number that will divide evenly into 18, 15, 12 6 peaches 5 apricots 4 plums

Linear-equations/268695: write the slope-intercept form of the equation of the line through the given points: through: (3,1) and (0,3) 1 solutions Answer 197383 by ankor@dixie-net.com(15652)   on 2010-02-13 19:22:41 (Show Source): You can put this solution on YOUR website! write the slope-intercept form of the equation of the line through the given points: through: (3,1) and (0,3) : Find the slope: = = Y intercept occurs when x = 0, therefore y = x + 3; the slope intercept form ; Check solution, replace x with 3: y = (3) + 3 y = -2 + 3 y = 1

Polygons/269206: I have been working on this math problem and don't know how to get the second part of it and I was wondering if someone could help me? Please and Thank you! I would deeply appreciate it! A team's best hitter has a lifetime batting average of .320. He has been at bat 325 times. He has made 104 hits. b. The same player goes into a slump and doesn't get any hits at all in his next ten times at bat. What is his current batting average to the nearest thousandth? 1 solutions Answer 197311 by ankor@dixie-net.com(15652)   on 2010-02-13 15:32:53 (Show Source): You can put this solution on YOUR website! Not hard, just add 10 to the times at bat and 0 to no. of hits = .310 batting average now

Numbers_Word_Problems/269156: When the digits of a two-digit number is 9 more than the original number, and the sum of the digits of the original number is 11. What is the original number? 1 solutions Answer 197298 by ankor@dixie-net.com(15652)   on 2010-02-13 13:47:38 (Show Source): You can put this solution on YOUR website! I think this problem should read: ; "When the digits of a two-digit number are reversed, the number is 9 more than the original number, and the sum of the digits of the original number is 11. What is the original number?" : Let x = the 10's digit Let y = the units the 10x + y = "the original two digit number : "When the digits of a two-digit number are reversed, the number is 9 more than the original number," 10y + x = 10x + y + 9 10y - y = 10x - x + 9 9y = 9x + 9 Simplify divide by 9 y = x + 1 : "the sum of the digits of the original number is 11. x + y = 11 Replace y with (x+1) x + x + 1 = 11 2x = 11-1 x = 5 then y = 5 + 1 = 6 : 56 is the original number ; : Check solution in the statement: "the digits of a two-digit number are reversed, the number is 9 more than the original number," 65 = 56 + 9

Rate-of-work-word-problems/269152: It takes 8 painters 6 hours to paint the walls of a gymnasium. a. How many person-hours does this job require? b. How many hours will 12 painters take to paint the gymnasium? 1 solutions Answer 197294 by ankor@dixie-net.com(15652)   on 2010-02-13 13:28:30 (Show Source): You can put this solution on YOUR website! It takes 8 painters 6 hours to paint the walls of a gymnasium. : a. How many person-hours does this job require? Person-hours??? Who comes up with these dumb terms?? : 8 * 6 = 48 MAN-hours, to do the job : b. How many hours will 12 painters take to paint the gymnasium? : Let x = no. of hours, when 12 men do the job 12x = 48 x = 48/12 x = 4 hrs to do the job

Linear-equations/269175: how do i put find the slope of linear equations by putting them in to slope-intercept form? i.e) 2x-4y=3 or probably y-3=2(x-2)please and thank you for your help 1 solutions Answer 197288 by ankor@dixie-net.com(15652)   on 2010-02-13 12:52:14 (Show Source): You can put this solution on YOUR website! how do i put find the slope of linear equations by putting them in to slope-intercept form? i.e) 2x-4y=3 : The slope/intercept form: y = mx + b; where m is the slope : 2x - 4y = 3 Subtract 2x from both sides -4y = -2x + 3 Divide both sides by 4 -y = x + y has to be positive, multiply both sides by -1 y = x - reduce the fraction y = x - ; this is the slope/intercept form, therefore slope (m) =

Miscellaneous_Word_Problems/269162: Three friends jog regularly in a park: Anna jogs every 10 days, Barbara jogs every 15 days, and Jo jogs every 14 days. One Sunday they happen to jog together. After how many days will the three friends jog together again? (A)150 (B) 210 (C) 350 (D) 420 (E) Never 1 solutions Answer 197287 by ankor@dixie-net.com(15652)   on 2010-02-13 12:45:24 (Show Source): You can put this solution on YOUR website! Three friends jog regularly in a park: Anna jogs every 10 days, Barbara jogs every 15 days, and Jo jogs every 14 days. One Sunday they happen to jog together. After how many days will the three friends jog together again? : Find a number that is a multiple of all three numbers 15 * 14 = 210, we know 10 is also a factor since it ends in 0 : 210 days is ans

Miscellaneous_Word_Problems/269169: What power of 16 is equal to 8 ? express your answer as a common fraction 1 solutions Answer 197279 by ankor@dixie-net.com(15652)   on 2010-02-13 11:31:28 (Show Source): You can put this solution on YOUR website! Find the 4th root of 16, (2) and cube that : 16^(3/4) = 8

Linear_Equations_And_Systems_Word_Problems/268817: Three batteries are connected in series so that the total voltage is 54 volts. The voltage of the first battery is twice the voltage of the second and 1/3 the voltage of the third battery. Find the actual voltage of each battery. 1 solutions Answer 197278 by ankor@dixie-net.com(15652)   on 2010-02-13 11:25:29 (Show Source): You can put this solution on YOUR website! Three batteries are connected in series so that the total voltage is 54 volts. The voltage of the first battery is twice the voltage of the second and 1/3 the voltage of the third battery. Find the actual voltage of each battery. : Let x = voltage of the 1st battery : " The voltage of the first battery is twice the voltage of the second", then: .5x = voltage of the 2nd battery : "and 1/3 the voltage of the third battery."which means: 3x = voltage of the third battery : Find the actual voltage of each battery. : x + .5x + 3x = 54 4.5x = 54 x = x = 12v is the 1st battery and .5(12) = 6v is the 2nd battery and 3(12) = 36v is the 3rd battery : : Check solution: 12 + 6 + 36 = 54

Quadratic_Equations/268745: victor threw a baseball into the air that modeled the equation h=-16t+36t+1,where h is the height in feet and t is the time in seconds.How long was the ball in the air if casey caught the ball 9 feet above the ground on its way down? 1 solutions Answer 197203 by ankor@dixie-net.com(15652)   on 2010-02-12 21:54:51 (Show Source): You can put this solution on YOUR website! victor threw a baseball into the air that modeled the equation h=-16t+36t+1,where h is the height in feet and t is the time in seconds.How long was the ball in the air if casey caught the ball 9 feet above the ground on its way down? : -16t^2 + 36t + 1 = 9 : -16t^2 + 36t + 1 - 9 = 0 : -16t^2 + 36t - 8 = 0 Simplify, change the signs, divide by -4 4t^2 - 9t + 2 = 0 Factors to (4t - 1)(t - 2) = 0 Two solutions 4t = 1 t = sec ; ball just off the bat and t = 2 sec; ball is caught at 9 ft

Travel_Word_Problems/268891: On Saturday morning, Lynn walked for 2 hours and then ran for 30 minutes. If she ran twice as fast as she walked and she covered 12 miles altogether,then how fast did she walk? 1 solutions Answer 197198 by ankor@dixie-net.com(15652)   on 2010-02-12 21:47:33 (Show Source): You can put this solution on YOUR website! On Saturday morning, Lynn walked for 2 hours and then ran for 30 minutes. If she ran twice as fast as she walked and she covered 12 miles altogether,then how fast did she walk? : Let s = L's walking speed then 2s = L's running speed : Write a dist equation: dist = time * speed : Walk dist + run dist = 12 mi 2s + .5(2s) = 12 2s + 1s = 12 3s = 12 s = s = 4 mph is L's walking speed ; ; Check solution in dist equation 2(4) + .5(8) = 12

Polynomials-and-rational-expressions/268894: A red ball and a green ball are simultaneously tossed into the air. The red ball is given an initial velocity of 96 feet per second, and its height t seconds after it is tossed is -16t^ 2 +96t feet. The green ball is given an initial velocity of 80 feet per second, and its height t seconds after it is tossed is-16t^2+ 80t feet. a) Find a polynomial D(t) that represents the difference in the heights of the two balls. b) How much higher is the red ball 2 seconds after the balls are tossed? c) In reality, when does the difference in the heights stop increasing? 1 solutions Answer 197194 by ankor@dixie-net.com(15652)   on 2010-02-12 21:40:27 (Show Source): You can put this solution on YOUR website! A red ball and a green ball are tossed into the air. The red ball is given an initial velocity of 96 feet per second and its height "t" seconds after it is tossed is -16t^2 + 96t feet. The green ball is given an initial velocity of 80 feet per second and its height "t" seconds after being tossed is -16t^2 +80t feet. : Find a polynomial D(t) that represents the difference in the heights of the two balls. D(t) = (-16t^2 + 96t) - (-16t^2 +80t) : Remove brackets D(t) = -16t^2 + 96t + 16t^2 - 80t : combine like terms: D(t) = 16t : How much higher is the red ball 2 seconds after the balls are tossed? D(t) = 16(2) D(t) = 32 ft difference after 2 seconds : When does the difference in the heights stop increasing? : Obviously, when one of the balls hits the ground : Find when the lowest ball hits the ground (h=0) -16t^2 + 80t = 0 Factor out -16t -16t(t - 5) = 0 t = 5 seconds when the difference stops increasing; : A graph illustrates this well

Travel_Word_Problems/268766: sherie rides her bike at 5 miles per hour. her sister leaves 15 minutes later cycling 8 miles per hour. long will it take her sister to catch up to sherie? 1 solutions Answer 197163 by ankor@dixie-net.com(15652)   on 2010-02-12 20:07:20 (Show Source): You can put this solution on YOUR website! sherie rides her bike at 5 miles per hour. her sister leaves 15 minutes later cycling 8 miles per hour. long will it take her sister to catch up to sherie? : Change 15 min to 15/60 = .25 hrs Let t = sister's travel time (in hrs) then (t+.25) = S's travel time : When sister catches S, they will have ridden the same distance. Write a distance equation: Dist = speed * time : sister's dist = S's dist 8t = 5(t+.25) 8t = 5t + 1.25 8t - 5t = 1.25 3t = 1.25 t = t = .4167 hrs or .4167 * 60 = 25 minutes to catch her : : Check solution by finding the dist of each, should be the same 8(.4167) = 3.33 mi 5(.4167+.25) = 3.33 mi

Square-cubic-other-roots/269028: Please help me solve this problem: Simplify by taking roots of the numerator and the denominator. Assume that all expressions under radicals represent positive numbers. 3 I dont know if I wrote the problem correctly but the 3 is the degree of the square root. thanks 1 solutions Answer 197160 by ankor@dixie-net.com(15652)   on 2010-02-12 19:54:12 (Show Source): You can put this solution on YOUR website! Simplify by taking roots of the numerator and the denominator. Assume that all expressions under radicals represent positive numbers. : 3 : Factor to reveal the perfect cubes inside the radical 3 : Extract those perfect cubes 3

Rate-of-work-word-problems/268616: Going into the final exam, which will count 2/3's of the final grade, Mike has test scores of 86, 80, 84, 90. What score does Mike need on the final in order to earn a B, which requires an average score of 80? What score would he need for an A? Do I simply find the average of the test scores and assume it's 1/3 of his final grade? Does it look like this: (85)1/3+ x2/3= 80 and to find his grade for an "A": 85(1/3)+ x2/3+90 Thank you! 1 solutions Answer 197156 by ankor@dixie-net.com(15652)   on 2010-02-12 19:33:19 (Show Source): You can put this solution on YOUR website! Going into the final exam, which will count 2/3's of the final grade, Mike has test scores of 86, 80, 84, 90. What score does Mike need on the final in order to earn a B, which requires an average score of 80?: : I think you can do it that way, this is the way I would do it: Average the 4 grades that represent 1/3 = 85 : x = 2/3 the final grade or twice as much as first 4 grades : = 80 multiply by 3 85 + 2x = 3(80) 2x = 240 - 85 2x = 155 x = x = 77.5 to get 80% for a B : Your way would get the same answer. : What score would he need for an A?

Polynomials-and-rational-expressions/268875: write alggebraic expressions for the follolwing 3 times the quantity of a number plus 8, 3 times the sum of a number and 8, half of the diffrence of the squares of a and b, five times a number is the same as that numbered square 1 solutions Answer 197155 by ankor@dixie-net.com(15652)   on 2010-02-12 19:17:30 (Show Source): You can put this solution on YOUR website! write alggebraic expressions for the follolwing 3 times the quantity of a number plus 8, 3x + 8 : 3 times the sum of a number and 8, 3(x+8) : half of the diffrence of the squares of a and b, (a^2 - b^2) : five times a number is the same as that number squared 5x = x^2

Volume/269018: A cone and a cylinder have the same volume and the same base radius. If you are given only the height of the cylinder, is it possible to figure out the height of the cone? If so, how would you figure it out 1 solutions Answer 197153 by ankor@dixie-net.com(15652)   on 2010-02-12 19:10:42 (Show Source): You can put this solution on YOUR website! A cone and a cylinder have the same volume and the same base radius. If you are given only the height of the cylinder, is it possible to figure out the height of the cone? If so, how would you figure it : The height of the cone would have to 3 times the height of the cylinder : We can illustrate this Let h = height of the cylinder Let 3h = height of the cone Cyl = Cone = If you cancel the denominator 3 into 3h you have the same formula

Miscellaneous_Word_Problems/268741: a 15-inch by 28-inch poster is to be framed using a border of uniform width. to make the framing visually appealing, the border should have an area equal to 60% of the area of the poster. how wide should the border be? 1 solutions Answer 197147 by ankor@dixie-net.com(15652)   on 2010-02-12 17:56:13 (Show Source): You can put this solution on YOUR website! a 15-inch by 28-inch poster is to be framed using a border of uniform width. to make the framing visually appealing, the border should have an area equal to 60% of the area of the poster. how wide should the border be? : Let x = the width of the border : Find the area of the poster: 15 * 28 = 420 sq/in : Find the area of the border .6(420) = 252 sq/in : The overall dimensions of poster and border: (2x+15) by (2x+28) : Overall area - poster area = border area (2x+15)*(2x+28) - 420 = 252 FOIL (4x^2 + 56x + 30x + 420) - 420 = 252 : 4x^2 + 86x + 420 - 420 = 252 : 4x^2 + 86x - 252 = 0; a quadratic equation : Use the quadratic formula to find the positive solution for x In this equation: a=4; b=86; c=-252 : : : : : x = x = 2.61 inches is the width of the border : : You can check solution: (15+5.22)*(28+5.22) - 420 = should equal 60% of 420

Polynomials-and-rational-expressions/268715: The members of a flying club plan to share equally the cost of a $200,000 airplane. The members want to find five more people to join the club so that the cost per person will decrease by $2000. How many members are currently in the club? 1 solutions Answer 197113 by ankor@dixie-net.com(15652)   on 2010-02-12 15:50:03 (Show Source): You can put this solution on YOUR website! The members of a flying club plan to share equally the cost of a $200,000 airplane. The members want to find five more people to join the club so that the cost per person will decrease by $2000. How many members are currently in the club? : Let x = no. of members currently : Let's do this in $1000's to avoid writing all these 0's; Plane cost 200, members want to save 2 : Present cost per member: Cost with 5 more members: : Present cost - cost with 5 more = 2 - = 2 Multiply equation by x(x+5), results : 200(x+5) - 200x = 2x(x+5) : 200x + 1000 - 200x = 2x^2 + 10x : 1000 = 2x^2 + 10x ; A quadratic equation 2x^2 + 10x - 1000 = 0 ; Simplify, divide by 2 x^2 + 5x - 500 ; Factor (x+25)(x-20) = 0 : Positive solution: x = 20 members now ; : Check this by finding the actual cost per member 200000/20 = $10000 With 5 more 200000/25 = $8000, 2 thousand less

Exponential-and-logarithmic-functions/268499: Solve algebraically: ln3+ln(x-6)=ln(x+5) 1 solutions Answer 197105 by ankor@dixie-net.com(15652)   on 2010-02-12 15:32:18 (Show Source): You can put this solution on YOUR website! Solve algebraically: ln3+ln(x-6)=ln(x+5) Adding logs means mult so we can write it: ln(3(x-6)) = ln(x+5) : ln(3x - 18) = ln(x + 5) therefore 3x - 18 = x + 5 : 3x - x = 5 + 18 : 2x = 23 : x = 11.5 ; : Check on a calc, the original equation enter: ln(3) + ln(11.5-6) results: 2.0833 enter: ln(11.5+5) results: 2.0833; equality confirms our solution of x = 11.5

Expressions-with-variables/268491: -1/2x=-7/8 whats x. i know to change the den to 8 and then multply 1 solutions Answer 197094 by ankor@dixie-net.com(15652)   on 2010-02-12 15:23:34 (Show Source): You can put this solution on YOUR website! x= whats x. : multiply both sides by 8, this gets rid of the denominators and results in: 4(-1)x = -7 -4x = -7 : The variable (x) has to be positive, multiply both sides by -1 4x = 7 : Divide both sides by 4 x = ; : Check solution in original equation *= =confirms your solution of x =

Linear_Equations_And_Systems_Word_Problems/268501: Please Complete the ordered pairs,(10) and (-10) , so that they satisfy the 1/5x-1/10y=4 equation . 1 solutions Answer 197090 by ankor@dixie-net.com(15652)   on 2010-02-12 15:15:31 (Show Source): You can put this solution on YOUR website! Please Complete the ordered pairs,(10) and (-10) , so that they satisfy the 1/5x-1/10y=4 equation . ; x - y = 4 Put the equation in the general y= form Multiply by 10, get rid of the denominators, results: 2x - y = 40 -y = -2x + 40 multiply both sides by -1 y = 2x - 40 : replace x with 10 to find y y = 2(10) - 40 y = -20 Ordered pair 10,-20 : replace x with -10 y = 2(-10) - 40 y = -60 Ordered pair: -10, -60

Equations/268507: I WRITE DOWN THREE CONSECUTIVE EVEN NUMBERS. SIX TIMES THE SMALLEST PLUS TWO TIMES THE LARGEST EQUALS SEVEN TIMES THE MIDDLE NUMBER. FIND THE THREE NUMBERS. 1 solutions Answer 197077 by ankor@dixie-net.com(15652)   on 2010-02-12 15:01:13 (Show Source): You can put this solution on YOUR website! I WRITE DOWN THREE CONSECUTIVE EVEN NUMBERS. x, (x+2), (x+4) ; SIX TIMES THE SMALLEST PLUS TWO TIMES THE LARGEST EQUALS SEVEN TIMES THE MIDDLE NUMBER. 6x + 2(x+4) = 7(x+2) 6x + 2x + 8 = 7x + 14 8x - 7x = 14 - 8 x = 6 is the smallest number : FIND THE THREE NUMBERS You can do that, I am sure.

Travel_Word_Problems/268597: The ambulance got a flat tire, so Action Man had to take Ed to the hospital. Action Man ran 22 mph, and Ed's dog followed behind, running 11 mph. If the dog took 7.5 minutes longer than Action Man to get there, how far away was the hospital? 1 solutions Answer 196928 by ankor@dixie-net.com(15652)   on 2010-02-11 21:54:03 (Show Source): You can put this solution on YOUR website! Action Man ran 22 mph, and Ed's dog followed behind, running 11 mph. If the dog took 7.5 minutes longer than Action Man to get there, how far away was the hospital? : Dog and man ran the same dist. write a dist equation: : Change 7.5 min to 7.5/60 = .125 hrs : Let t = Man's running time, then (t+.125) = dog's running time : 22t = 11(t+.125) 22t = 11t + 1.375 22t - 11t = 1.375 11t = 1.375 t = t = .125 hrs Dist = 22 * .125 = 2.75 mi to hospital

Travel_Word_Problems/268596: Action Man was eating in a diner when his super-powered ears heard someone 2 miles away yelling for help. He rushed outside and ran to the man (named ED) who had fallen from a tree. Six minutes after he arrived, an ambulance pulled up that had driven 12 miles to the scene. If the ambulance drove 3 times as fast as Action Man ran, how long did it take Action Man to get to Ed? 1 solutions Answer 196927 by ankor@dixie-net.com(15652)   on 2010-02-11 21:43:57 (Show Source): You can put this solution on YOUR website! Action Man was eating in a diner when his super-powered ears heard someone 2 miles away yelling for help. He rushed outside and ran to the man (named ED) who had fallen from a tree. Six minutes after he arrived, an ambulance pulled up that had driven 12 miles to the scene. If the ambulance drove 3 times as fast as Action Man ran, how long did it take Action Man to get to Ed? : Let s = A-man's speed then 3s = Amb speed : Change 6 min to 6/60 = .1 hrs : Write a time equation: Time = dist/speed : A-man's time + .1 hr = Amb time + .1 = + .1 = ; reduced fraction multiply by s 2 + .1s = 4 .1s = 4 - 2 .1s = 2 s = s = 20 mph is A-man's speed then = .1 hrs which is 6 minutes for A-man to run two miles : : You can confirm this by finding the time for the amb to come 3(20) = 60 mph is amb speed, would take 12 min to go 12 mi, 6 min after A-man

Divisibility_and_Prime_Numbers/268718: a group of children walk to a corner store and buy cans of soda for a total of $3.36 and candy bars for a total of $2.45. Each child has one can of soda and one candy bar. How many children were in the group> What is the cost of one can of soda nd one cany bar? 1 solutions Answer 196918 by ankor@dixie-net.com(15652)   on 2010-02-11 21:10:12 (Show Source): You can put this solution on YOUR website! a group of children walk to a corner store and buy cans of soda for a total of $3.36 and candy bars for a total of $2.45. Each child has one can of soda and one candy bar. How many children were in the group> What is the cost of one can of soda and one candy bar? : Lets do this in cents, 336 and 245 Find the common prime factors 336: 2*2*2*2*3*7 245: 5*7*7 : The common factor is 7, therefore: 7 children in the group : 336/7 = 48 cents for a soda 245/7 = 35 cents for a candy bar

Travel_Word_Problems/268621: An air rescue plane averages 300 miles per hour in still air. It carries enough fuel for 5 hours of flying time. If, upon takeoff it encounters a head wind of 30 mi/hr and the wind remains constant, how far can the plane fly and then return safely? Is the rate simply 300-30? How do I find the distance traveled? 1 solutions Answer 196911 by ankor@dixie-net.com(15652)   on 2010-02-11 20:50:32 (Show Source): You can put this solution on YOUR website! An air rescue plane averages 300 miles per hour in still air. It carries enough fuel for 5 hours of flying time. If, upon takeoff it encounters a head wind of 30 mi/hr and the wind remains constant, how far can the plane fly and then return safely? : Effective ground speed 300 - 30 = 270 mph against the wind 300 + 30 = 330 mph with the wind : Let d = the one-way distance; write a time equation, time = dist/speed : outbound time + return time = 5 hrs + = 5 Multiply by 81900 (270*330), eliminate the denominators, results: 330d + 270d = 5(81900) 600d = 445500 6d = 4455 d = d = 742.5 mi, the plane can fly out and return safely : : Check this by finding the total time 742.5/270 + 742.5/330 = 2.75 + 2.25 = 5