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# Recent problems solved by 'checkley77'

checkley77 answered: 12560 problems
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 Miscellaneous_Word_Problems/325255: This is the word problem. Thanks!: Jane and Tariq took a canoeing trip, traveling 6 mi upsteam against a 2 mi/h current. They then returned to the same point downstream. If their entire trip took 4 h, how fast can they paddle in still water? (Hint: If r is their rate, in mi/h, in still water, their rate upstream is r-2 and their rate dwonstream is r+2)1 solutions Answer 232903 by checkley77(12569)   on 2010-07-24 17:31:12 (Show Source): You can put this solution on YOUR website!D=RT T=D/R 4=6/(R+2)+6(R-2) 4=[6(R-2)+6(R+2)]/(R+2)(R-2) 4=(6R-12+6R+12)/(R^2-4) 4=12R/(R^2-4) 4(R^2-4)=12R 4R^2-16-12R=0 4R^2-12R-16=0 4(R^2-3R-4)=0 4(R-4)(R+1)=0 R-4=0 R=4 ANS FOR THE RATE OF THE CANOE IN STILL WATER. PROOF: 4=6/(4+2)+6/(4-2) 4=6/6+6/2 4=1+3 4=4
 Linear_Equations_And_Systems_Word_Problems/324947: the area of a rectangle is 135 in^2 the length is 6 inches shorter than the width find the length1 solutions Answer 232825 by checkley77(12569)   on 2010-07-23 22:31:11 (Show Source): You can put this solution on YOUR website!L=W-6 A=LW 135=(W-6)W 135=W^2-6W W^2-6W-135=0 (W+9)(W-15)=0 W-15=0 W=15 ANS. FOR THE WIDTH. L=15-6=9 ANS. FOR THE LENGTH. PROOF: 135=15*9 135=135
 Mixture_Word_Problems/325044: a rental car place rents out cars. barney is charged \$111 for 3 days and 300 miles, mary is charged \$207 for 5 days and 600 miles. what do they charge per day and per mile?1 solutions Answer 232823 by checkley77(12569)   on 2010-07-23 22:25:54 (Show Source): You can put this solution on YOUR website!3D+300M=111 MULTIPLY BY 2 5D+600M=207 MULTIPLY BY -1 & ADD 6D+600M=222 -5D-600M=-207 ---------------- D=\$13 PER DAY 3*15+300M=111 45+300M=111 300M=111-45 300M=66 M=66/300 M=\$.22 PER MILE. PROOF: 5*15+600*.22=207 75+132=207 207=207
 Polynomials-and-rational-expressions/325054: A 20-ft by 40-ft pool is surrounded by a deck d feet wide. What is the combined area of the deck and the pool?1 solutions Answer 232819 by checkley77(12569)   on 2010-07-23 22:12:28 (Show Source): You can put this solution on YOUR website!(20+2D)(40+2D) 800+80D+40D+4D^2 4D^2+120D+800 4(D^2+30D+200) ANS.
 Quadratic_Equations/325075: 2w(4w+1)=11 solutions Answer 232818 by checkley77(12569)   on 2010-07-23 22:04:08 (Show Source): You can put this solution on YOUR website!2w(4w+1)=1 8W^2+2W-1=0 (4W-1)(2W+1)=0 4W-1=0 4W=1 W=1/4 OR .25ANS. 2W+1=0 2W=-1 W=-1/2 OR -.5 ANS.
 Quadratic_Equations/325096: John likes dark coffe beans, which cost \$8.50/kg. Brad likes mild coffe beans which cost \$9.20/kg. They buy a 5.5kg made from a blend of both type of beans that cost \$48.50. How many kg of each type of bean went into the mixture?1 solutions Answer 232816 by checkley77(12569)   on 2010-07-23 21:58:21 (Show Source): You can put this solution on YOUR website!9.20X+8.50(5.5-X)=48.50 9.20X+46.75-8.50X=48.50 .70X=48.50-46.75 .70X=1.75 X=1.75/.70 X=2.5 LBS. OF \$9.20 COFFEE. 5.5-.5=3 LBS OF \$8.50 COFFEE. PROOF: 9.20*2.5+8.50*3=48.50 23+25.5=48.50 48.50=48.50
 Equations/325105: The equation D=1.2 sqrt h gives the distance, D, in miles that a person can see to the horizon from a distance height h in feet assuming I have the equation solved for h correct sqrt h= d/1.2=h=d^2/1.44=36d^2/25 how do I solve this problem Long's Peak in Rocky Mount National Park is 14,255 ft. in elevation. How far can you see the horizon from the top? Cn you see Cheyene Wy. which is about 89 miles away?1 solutions Answer 232812 by checkley77(12569)   on 2010-07-23 21:50:50 (Show Source): You can put this solution on YOUR website!D=1.2*SQRTH D=1.2*SQRT14,255 D=1.2*119.39 D=142.26 MILES. YES YOU COULD SEE CHEYENE.
 Exponents/324828: for all x 36x4-8x3-28x2=1 solutions Answer 232557 by checkley77(12569)   on 2010-07-22 19:13:22 (Show Source): You can put this solution on YOUR website!36x^4-8x^3-28x^2=0 4x^2(9x^2-2x-7)=0 4x^2(9x+7)(x-1)=0 4x^2=0 x=0 ans. 8x+7=0 9x=-7 x=-7/9 ans. x-1=0 x=1 ans.
 Sequences-and-series/324829: What is next in this sequence and how do I solve probems like this, is there a formula? 1 5 14 30 55 91 1401 solutions Answer 232555 by checkley77(12569)   on 2010-07-22 19:07:41 (Show Source): You can put this solution on YOUR website!1 5 14 30 55 91 140 Calculate the difference between each value. 4 9 16 25 36 49 these are the squares of 2,3,4,5,6 & 7 Thus the next number will be 140+8^2=140+64=204.
 Quadratic_Equations/324724: x^2 + 2/3x + ____ = (x + ____)^21 solutions Answer 232550 by checkley77(12569)   on 2010-07-22 18:47:49 (Show Source): You can put this solution on YOUR website!x^2 + 2/3x + 1/9 = (x +1/3)^2 ans.
 Rectangles/324790: one side of a rectangle is 2cm longer than a second side. If the area is 35cm squared, find the dimensions of the rectangle.1 solutions Answer 232548 by checkley77(12569)   on 2010-07-22 18:43:17 (Show Source): You can put this solution on YOUR website!L=W+2 A=LW 35=(W+2)W 35=W^2+2W W^2+2W-35=0 (W+7)(W-5)=0 W-5=0 W=5 ANS. FOR THE WIDTH. L=5+2=7 ANS. FOR THE LENGTH. PROOF: 35=7*5 35=35
 Rectangles/324811: The length of a rectangle is 4 cm longer than the width. If the perimeter is 20 cm, what is the area of the rectangle?1 solutions Answer 232547 by checkley77(12569)   on 2010-07-22 18:37:06 (Show Source): You can put this solution on YOUR website!L=W+4 P=2L+2W 20=2(W+4)2W 20=2W+8+2W 20=4W+8 4W=20-8 4W=12 W=12/4 W=3 ANS. FOR THE WIDTH. L=3+4=7 ANS. FOR THE LENGTH. PROOF: 20=2*7=2*3 20=14+6 20=20
 Angles/324825: the measures of two complementary angles are in the ratio 4:1. what is the measure of the smaller angle?1 solutions Answer 232546 by checkley77(12569)   on 2010-07-22 18:31:57 (Show Source): You can put this solution on YOUR website!4R+1R=5R 5R=90 R=90/5 R=18 DEGREES ANS. FOR THE SMALLER ANGLE. 4R=4*18=72 DEGREES FOR THE LARGER ANGLE. PROOF: 18+72=90 4:1=72:18 72=4*18 72=72
 Square-cubic-other-roots/324685: Solve by the square root property x^2=18 Give the answer in radical form and NOT as a decimal.1 solutions Answer 232544 by checkley77(12569)   on 2010-07-22 18:24:51 (Show Source): You can put this solution on YOUR website!x^2=18 X^2=9*2 X=SQRT(9+2) X=3SQRT2 ANS.
 Polynomials-and-rational-expressions/324689: The base of a triangle is 4cm greater than the height. the area is 48cm^2. Find the height and length of the base! Thank you1 solutions Answer 232542 by checkley77(12569)   on 2010-07-22 18:21:58 (Show Source): You can put this solution on YOUR website!B=H+4 A=BH/2 48(H+4)H/2 48=(H^2+4H)/2 H^2+4H=48*2 H^2+4H=96 H^2+4H-96=0 (H+12)(H-8)=0 H-8=0 H=8 ANSWER FOR THE HEIGHT. B=8+4=12 ANS. FOR THE HEIGHT. PROOF: 48=8*12/2 48=96/2 48=48
 Numbers_Word_Problems/324693: There were 24 coins and a balance scale. The coins are identical in every way except that one of them is counterfeit and slightly heavier than the other 23 coins. What is the least number of weighings needed on the balance scale to determine which is the heavier coin?1 solutions Answer 232540 by checkley77(12569)   on 2010-07-22 17:53:37 (Show Source): You can put this solution on YOUR website!FIRST TRY 12 & 12 SELECT THE HEAVIEST SIDE SECOND TRY 6 & 6 DITTO THIRD TRY 3 & 3 WEIGH 2 OF THE HEAVIEST SIDE. IF ONE WEIGHS MORE - YOU"VE FOUND IT. IF THEY MATCH - THE THIRD COIN IS THE HEAVIEST. THUS 4 TRIES ARE NEEDED.
 Polynomials-and-rational-expressions/324713: (2x+3y-4)-(x-y-2)1 solutions Answer 232538 by checkley77(12569)   on 2010-07-22 17:46:45 (Show Source): You can put this solution on YOUR website!(2x+3y-4)-(x-y-2) 2X-X+3Y+Y-4+2 X+4Y-2 ANS.
 Numbers_Word_Problems/324728: 1.find two consecutive even numbers such that 5 times the first exceeds 3 times the second by 54 2.China,USA and France are the thre most popular travel destinations, USA has 9 million more visitors than France, and China has 44 million more vistors than France. If the total number of tourisits in these three countries is 332 million, how many visited each country?1 solutions Answer 232537 by checkley77(12569)   on 2010-07-22 17:44:33 (Show Source): You can put this solution on YOUR website!X, X+2 ARE THE 2 CONSECUTIVE EVEN NUMBERS. 5X=3(X+2)+54 5X=3X+6+54 5X-3X=60 2X=60 X=60/2 X=30 ANS. FOR THE SMALLER NUMBER. 30+2=32 ANS. FOR THE LARGER NUMVBER. PROOF: 5*30=3*32+54 150=96+54 150=150
 Rate-of-work-word-problems/324767: there are three house painters painting the same house. one paints it in two hours and the next in three hours the third painter paints the house in five hours how long would it take all three of them to work together and paint the house.1 solutions Answer 232535 by checkley77(12569)   on 2010-07-22 17:36:41 (Show Source): You can put this solution on YOUR website!1/2+1/3+1/5=1/X FIND THE LCD (2*3*5=30) (15+10+6)/30)=1/X 31/30=1/X 31X=30 X=30/31 X=.97 HOURS.
 Rational-functions/324801: If f(x) = 7x3 − 8x + 2, then f(8) = ___.1 solutions Answer 232529 by checkley77(12569)   on 2010-07-22 16:53:06 (Show Source): You can put this solution on YOUR website!If f(x) = 7x3 − 8x + 2, then f(8) f(8)=7*8^3-8*8+2 f(8)=7*512-64+2 f(8)=3,584-62 f(8)=3,522 ans.
 Probability-and-statistics/324456: Assume that a blood pressure range between 149 and 159 is randomly selected, find the probability that the given blood pressure level is selected is between 153 and 158.51 solutions Answer 232248 by checkley77(12569)   on 2010-07-21 19:02:07 (Show Source): You can put this solution on YOUR website!(158.5-153)/(159-149) 5.5/10=.55 OR 55% ANS.
 Rectangles/324472: The length of a rectangles is 4cm longer than the width. If the perimeter of the rectangle is 20 centimeters, what is the area of the rectangle?1 solutions Answer 232246 by checkley77(12569)   on 2010-07-21 18:57:21 (Show Source): You can put this solution on YOUR website!L=W+4 P=2L+2W 20=2(W+4)+2W 20=2W+8+2W 20=4W+8 4W=20-8 4W=12 W=12/4 W=3 ANS. FOR THE WIDTH. L=3+4=7 ANS. FOR THE LENGTH. PROOF: 20=2*3+2*7 20=6+14 20=20
 Numbers_Word_Problems/324461: One positive number is 4 more than 3 times another positive number. The product of the numbers is 7. What are the two numbers? 1 solutions Answer 232245 by checkley77(12569)   on 2010-07-21 18:50:34 (Show Source): You can put this solution on YOUR website!X=3Y+4 XY=7 (3Y+4)Y=7 3Y^2+4Y=7 3Y^2+4Y-7=0 (3Y+7)(Y-1)=0 Y-1=0 Y=1 ANS. X=3*1+4 X=3+4=7 ANS. PROOF: 7*1=7 7=7
 Geometry_Word_Problems/324469: the length of a rectangle is 4meters greater than its width. the area is 96 meters square. what is the length and width1 solutions Answer 232244 by checkley77(12569)   on 2010-07-21 18:42:27 (Show Source): You can put this solution on YOUR website!L=W+4 A=LW 96=(W+4)W 96=W^2+4W W^2+4W-96=0 (W-8)(W+12)=0 W-8=0 W=8 ANS. FOR THE WIDTH. L=8+4=12 ANS. FOR THE LENGTH. PROOF: 96=8*12 96=96
 Rectangles/324483: A rectangular flower bed is eight feet longer than it is wide. If the area of the flower bed is 84 square feet, find the width and the length of the flower bed.1 solutions Answer 232243 by checkley77(12569)   on 2010-07-21 18:26:29 (Show Source): You can put this solution on YOUR website!L=W+8 A=LW 84=(W+8)W 84=W^2+8W W^2+8W-84=0 (W+14)(W-6)=0 W-6=0 W=6 ANS. FOR THE WIDTH. L=6+8=14 ANS. FOR THE LENGTH. PROOF: 84=6*14 84=84
 Polynomials-and-rational-expressions/324488: Solve -x^2-2x+8=o Can you please help me?1 solutions Answer 232241 by checkley77(12569)   on 2010-07-21 18:22:02 (Show Source): You can put this solution on YOUR website!-x^2-2x+8=0 (-x-4)(x-2)=0 -x-4=0 -x=4 x=4/-1 x=-4 ans. x-2=0 x=2 ans.
 Polynomials-and-rational-expressions/324490: Factor completley 2s^2-7s+5 Tank you1 solutions Answer 232240 by checkley77(12569)   on 2010-07-21 18:15:30 (Show Source): You can put this solution on YOUR website!2s^2-7s+5 (2s-5)(s-1) ans
 Polynomials-and-rational-expressions/324491: Factor by grouping x^3+5x^2-3x-15 Thank you1 solutions Answer 232238 by checkley77(12569)   on 2010-07-21 18:12:38 (Show Source): You can put this solution on YOUR website!x^3+5x^2-3x-15 x^2(x+5)-3(x+5) (x^2-3)(x+5) ans.
 Polynomials-and-rational-expressions/324492: Divide and check, write your answer using nonnegative exponents 6x^4y^2 divided by 2x^6y^21 solutions Answer 232237 by checkley77(12569)   on 2010-07-21 18:10:54 (Show Source): You can put this solution on YOUR website!6x^4y^2/2x^6y^2 6/3=2 x^4/x^6 1/x^(6-4)=1/x^2 y^2/y^2=1 2/x^2 ans.
 Rectangles/324217: If the area of triangle abc is 114 square units and h = 12, calculate the value of b. 1 solutions Answer 232056 by checkley77(12569)   on 2010-07-20 20:35:57 (Show Source): You can put this solution on YOUR website!A=B*H/2 114=B*12/2 114=12B/2 12B=2*114 12B=228 B=228/12 B=19 UNITS FOR THE BASE. PROOF: 114=19*12/2 114=228/2 114=114
 Expressions-with-variables/324219: The sum of 2 numbers is -1. ( X + Y = -1 ) Five times the first number equals 3 times the second number. Find the 2 numbers.1 solutions Answer 232053 by checkley77(12569)   on 2010-07-20 20:30:47 (Show Source): You can put this solution on YOUR website!X+Y=-1 5X=3Y OR X=3Y/5 3Y/5+Y=-1 (3Y+5Y)/5=-1 8Y/5=-1 8Y=-5 Y=-5/8 AMS. X=3(-5/ 8)/5 X=(-15/8)/5 X=-15/8*1/5 X=-3/8 X=-3/8 ANS.