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The canoiest travels 9 mls. on the second part of the trip. at a speed of 5 mls. slower. The total time for this trip is 2 hrs. What was the speed on each part of the trip? 1 solutions
Answer 336928 by mananth(12270) on 2011-09-15 02:39:57 (Show Source):
You can put this solution on YOUR website!first part 35 miles
second part 9 miles
speed in first part x mph
speed second part x -5 mph
Total rowing time 2 hours
Time first part 35 / x
Time second part 9 / ( x -5 )
Time first part + time second part = 2 hours
35 / x + 9 /(x -5 ) = 2
LCD = ( x + 0 )* (x -5 )
multiply the equation by the LCD
we get
35 * (x -5 )+ 9 x = 2
35 x -175 + 9 x = 2 X^2 + -10 x
54 x -175 = 2 X^2
2 X^2 -54 x 175 = 0
2 X^2+ -54 x+ 175 =
/ 2
1 X^2 -27 x 87.5 =
Find the roots of the equation by quadratic formula
a= 1 b= -27 c= 87.5
b^2-4ac= 729 - -350
b^2-4ac= 379  = 19.47
x1=( 27 + 19.47 )/ 2
x1= 23.23 mph
x2=( 27 -19.47 ) / 2
x2= 3.77 mph
First Part speed = 23.23 mph
Second part speed = 18.23 mph
m.ananth@hotmail.ca
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Money_Word_Problems/498162: kate invests money in two plans. She invests three-fifths of the money in an account at a return rate of 2%. She invests the remainder of the money in an account with a return rate of 4%. If the total interest earned in one year from investments is $84,00, how much was invested in each plan? 1 solutions
Answer 336927 by mananth(12270) on 2011-09-15 02:28:52 (Show Source):
You can put this solution on YOUR website!let total money invested be x
3x/5 ----------- 2%
2x/5-------------4%
interest
3x/5 * 0.02 + 2x/5* 0.04 = 84
0.06x/5 +0.08x/5 = 84
0.14x=5*84
0.14x=420
x= 420/0.14= 3000
2%----------- 3*3000/5 = 1800
4%------------2*3000/5 = 1200
m.ananth@hotmail.ca
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Linear-systems/498172: Solve the stem of linear equations. What is the x and y answer to this problem?
2x + y = 4
x - y = 2
1 solutions
Answer 336924 by mananth(12270) on 2011-09-15 02:05:03 (Show Source):
You can put this solution on YOUR website!2 x + 1 y = 4 .............1
1 x -1 y = 2 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by 1
2 x 1 y = 4
1 x -1 y = 2
Add the two equations
3 x = 6
/ 3
x = 2
plug value of x in (1)
2 x + 1 y = 4
4 + 1 y = 4
1 y = 4 -4
1 y = 0
y = 0
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Linear-systems/498173: Solve the stem of linear equations. What is the x and y answer to this problem?
y - 2x = 0
6y + 2x = 0 1 solutions
Answer 336923 by mananth(12270) on 2011-09-15 02:03:30 (Show Source):
You can put this solution on YOUR website!-2 x + 1 y = 0
2 x + 6 y = 0
Eliminate y
multiply (1)by -6
Multiply (2) by 1
12 x -6 y = 0
2 x 6 y = 0
Add the two equations
14 x = 0
/ 14
x = 0
plug value of x in (1)
-2 x + 1 y = 0
0 + 1 y = 0
1 y = 0
1 y = 0
y = 0
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Mixture_Word_Problems/497543: Manuel traveled 5 hours nonstop to mexico, a total of 293 miles. He took a train part of the way, which averaged 70mph, and then took a bus the remaining distance, which averaged 40mph. how long was manuel on the train? 1 solutions
Answer 336752 by mananth(12270) on 2011-09-14 10:19:33 (Show Source):
You can put this solution on YOUR website!Train x miles --------- 70 mph
Bus 293-x miles---------40 mph
time train + time bus = 5
t=d/r
x/70 + (293-x)/40 = 5
Multiply by LCD 2800
40x+70(293-x)= 5 * 2800
-30x+20510=14000
-30x=-6510
x=-6510/-30
x=217----------- train distance
balance bus distance
m.ananth@hotmail.ca
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Mixture_Word_Problems/497536: Shanika has invested in 3 different stocks. Stock A is currently worth $4.50 per share. Stock B is worth $7.00 per share, while stock C is worth $10.00 per share. Shanika purchased half as many shares of stock B as stock A and half as many shares of stock C as stock B. If her total investments are currently worth %546, how many shares of each stock does she own? 1 solutions
Answer 336750 by mananth(12270) on 2011-09-14 10:09:57 (Show Source):
You can put this solution on YOUR website!Stock A = x-----------------4.50
Stock B = x/2---------------7.00
Stock C = x/4---------------10.00
Total investment = 546
4.5x+7*(x/2)+10*(x/4)=546
multiply by 4
18x+14x+10x=2184
42x=2184
x=52 ----------- A
26----------------B
13----------------C
CHECK
52*4.5+26*7+13*10=546
m.ananth@hotmail.ca
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Money_Word_Problems/497529: A sum of $2,450 is invested, part of it at 11% interest and the remainder at 14%. If the interest earned by the 14% investment is $100 more than the interest earned by the 11% investment, find the amount invested at each rate.
Can you show work?? 1 solutions
Answer 336748 by mananth(12270) on 2011-09-14 09:44:30 (Show Source):
You can put this solution on YOUR website!Part I 11.00% per annum ------------- x
Part II 14.00% per annum ------------ y
total investment 2450
Interest----- 11.00% x
Interest = 14.00% y greater by 100
11.00% x = 14.00% y + 100
multiply by 100
11 x - 14 y = 10000 --------1
x + y = 2450 -------- 2
eliminate y
Multiply 1 by 1
Multiply 2 by 14
we get
11 x -14 y = 10000
14 x +14 y = 34300
25 x = 44300
/ 25
x= 1772
Plug the value of x in in 1
19492 -14 y = 10000
-14 y = 10000 -19492
-14 y = -9492
/ -14
y= 678
$ 1772 at 11.00%
$ 678 at 14.00%
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Mixture_Word_Problems/497522: how much of a 60% orange juice drink must be mixed with 4 gallons of a 30% orange juice drink to obtain a mixture of 50% orange juice? 1 solutions
Answer 336743 by mananth(12270) on 2011-09-14 09:23:40 (Show Source):
You can put this solution on YOUR website! percent ---------------- quantity
Orange juice I 30 ---------------- 4 gallons
Orange juice II 60 ---------------- x gallons
Mixture 50 ---------------- 4 + x gallons
30 * 4 + 60 x = 50 ( 4 + x )
120 + 60 x = 200 + 50 x
60 x + -50 x = 200 - -120
10 x = 80
/ 10
x = 8
8 gallons of 60 % Orange juice II II
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Travel_Word_Problems/497518: A bird travels at 500 mph and leaves 10 minutes before his bird friend, which travels at 1500 mphs. How long does it take the friend bird to catch up to the bird that left 10 minutes before him? ... ANSWER NOW IM CURRENTLY IN MY MATH CLASS AND IN BIG TROUBLE IF YOU DONT ANSWER THIS!! 1 solutions
Answer 336742 by mananth(12270) on 2011-09-14 09:20:26 (Show Source):
You can put this solution on YOUR website!Bird I 500 mph
Bird II 1500 mph
In 10 minutes = 1/6 hour bird I travels 500*1/6 = 83.33 miles.
difference between their speeds = 1000
d= 83.33
speed = 1000 mph
time = d/r
83.33/1000
0.0833 hours
0.0833*3600= 300 seconds
time to catchup = 300 seconds
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Mixture_Word_Problems/497497: How much 10% acid solution and 30% acid solution should be mixed together to yield 100 liters of a 25% acid solution? 1 solutions
Answer 336741 by mananth(12270) on 2011-09-14 09:14:23 (Show Source):
You can put this solution on YOUR website!acid percentage ---------------- quantity
Acid I 10 ---------------- x liters
Acid II 30 ---------------- 100 - x liters
Mixture 25.00% ---------------- 100
10x+30(100-x)=25 * 100
10x +3000 -30x= 2500
10x-30x =2500 - 3000
-20 x= -500
/ -20
x=25 liters 10.00% Acid I
75 liters 30.00% Acid II
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Mixture_Word_Problems/497505: How much 10% acid solution and 30% acid solution should be mixed together to yield 100 liters of a 25% acid solution? 1 solutions
Answer 336740 by mananth(12270) on 2011-09-14 09:12:22 (Show Source):
You can put this solution on YOUR website!percent percentage ---------------- quantity
Acid I 10 ---------------- x liters
Acid II 30 ---------------- 100 - x liters
Mixture 25.00% ---------------- 100
10x+30(100-x)=25 * 100
10x +3000 -30x= 2500
10x-30x =2500 - 3000
-20 x= -500
/ -20
x=25 liters 10.00% Acid I
75 liters 30.00% Acid II
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Angles/497510: An angle is 20 degrees more than four time its complement, how do I figure this out? I know what a complement is, I just don't know how to figure this problem out since I wasn't given an original degree.
Also:
Find the supplement of angle A if m(A = 3x + 50.
How do I figure this out as well?
I am not looking for the answer, unless you are going to provide me with detailed steps with it. I am looking for an explanation on how to figure it out this way I can figure out other similar problems! Please don't just hand me an answer I need steps and thorough explanations that I can understand! Thank you! 1 solutions
Answer 336739 by mananth(12270) on 2011-09-14 09:02:09 (Show Source):
You can put this solution on YOUR website!let angle be x
complement = (90-x)
4 times = 4 (90-x)
20 more
x= 4(90-x)+20
x=360-4x+20
5x=380
x=76
m(A) = 3x+50
supplement = 180-(3x+50)
=180-3x-50
=130-3x
...
CHECK
add them up you get 180 deg
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Travel_Word_Problems/497459: a boat travel 10 kilometer. upstream and 10 kilometer. back. the trip upstream and back takes 1.5 hours. If the speed of the current is 5 kilometer. per hour what is the speed of the boat in still water 1 solutions
Answer 336736 by mananth(12270) on 2011-09-14 05:41:50 (Show Source):
You can put this solution on YOUR website!Boat speed x
current speed 5
against current x- 5 kph
with current x+ 5 kph
Distance= 10 km
Time against + time with = 1.5 hours
10 /( x + 5 ) + 10 /(x - 5 ) = 1.5
LCD = (x - 5 ) ( x + 5 )
10 *( x - 5 ) + 10 (x + 5 ) = 1.5
10 x - 50 + 10 x + 50 = 1.5 ( x ^2 - 25 )
20 x = 1.5 x ^2 - 37.5
1.5 x ^2 - -20 x - 37.5
Find the roots of the equation by quadratic formula
a= 1.5 , b= -20 , c= -37.5
b^2-4ac= 400 + 225
b^2-4ac= 625
x1=( 20 + 25 )/ 3
x1= 15
x2=( 20 -25 ) / 3
x2= -1.67
Ignore negative value
15 mph=speed of boat
m.ananth@hotmail.ca
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Travel_Word_Problems/497378: A freight train leaves a station and travels north at 55 mph. Four hours later, a passenger train leaves on a parallel track and travels north at 66 mph. How long will it take the passenger train to overtake the freight train? 1 solutions
Answer 336714 by mananth(12270) on 2011-09-13 23:45:03 (Show Source):
You can put this solution on YOUR website!Freight train 55 mph
Passenger train 66 mph
Freight train 02:00
Passenger train 06:00
Difference in time= 04:00 => 4 hours
Freight train will have covered 220 miles before Passenger train starts from station
catch up distance= 220 miles
catch up speed = 66 -55 mph
catch up speed = 11 mph
Catchup time = catchup distance/catch up speed
catch up time= 220 / 11
catch up time= 20 hours
m.ananth@hotmail.ca
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Problems-with-consecutive-odd-even-integers/496721: Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this.
-2x + 6y = -12
x + 3y = -3
1 solutions
Answer 336536 by mananth(12270) on 2011-09-13 09:22:45 (Show Source):
You can put this solution on YOUR website!-2 x + 6 y = -12 .............1
1 x + 3 y = -3 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by -2
-2 x 6 y = -12
-2 x -6 y = 6
Add the two equations
-4 x = -6
/ -4
x = 1.50 OR 1 1/ 2
plug value of x in (1)
-2 x + 6 y = -12
-3 + 6 y = -12
6 y = -12 + 3
6 y = -9
y = -1.50 OR
m.ananth@hotmail.ca
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Problems-with-consecutive-odd-even-integers/496722: Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this.
-3x + 4y = -19.5
-3x + y = -10.5
1 solutions
Answer 336535 by mananth(12270) on 2011-09-13 09:20:40 (Show Source):
You can put this solution on YOUR website!-3 x + 4 y = -19.5 .............1
-3 x + 1 y = -10.5 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by -4
-3 x 4 y = -19.5
12 x -4 y = 42
Add the two equations
9 x = 22.5
/ 9
x = 2.50 OR 2 1/ 2
plug value of x in (1)
-3 x + 4 y = -19.5
-7.5 + 4 y = -19.5
4 y = -19.5 + 7.5
4 y = -12
y = -3
(5/2,-3)
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Problems-with-consecutive-odd-even-integers/496723: Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this.
-x + 6y = 54
3x + y = 9
1 solutions
Answer 336534 by mananth(12270) on 2011-09-13 09:18:14 (Show Source):
You can put this solution on YOUR website!-1 x + 6 y = 54 .............1
1 y = 9 -3 x ---------2
/ 1 =
y = 9 -3 x
Substitute y in (1)
-1 x + 6 ( 9 -3 x ) = 54
-1 x + 54 + -18 x = 54
-1 x -18 x = 54 -54
-19 x = 0
/ -19
x= 0
Plug the value of x in (1)
-1 x + 6 y = 54
-1 * 0 + 6 y = 54
0 + 6 y = 54
6 y = 54
/ 6
y= 9
Solution (0,9)
m.ananth@hotmail.ca
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Numbers_Word_Problems/496725: write the english phrase as an algebraic expression, then simplify the expression. Let x represent the number.
seven increased by the product of 2 and one less than a number 1 solutions
Answer 336533 by mananth(12270) on 2011-09-13 09:14:55 (Show Source):
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Travel_Word_Problems/492720: two automobiles set out simultaneously from places 100 miles apart. they traveled toward each other and passed at the end of 1 hour and 40 minutes. the speed of one automobile was 5 miles per hour greater than of the other. find the speed of each. can you please answer it for me? thanks! 1 solutions
Answer 335164 by mananth(12270) on 2011-09-07 06:20:39 (Show Source):
You can put this solution on YOUR website!Distance they meet from one car = x
other car travels 100-x miles when they meet.
distance/time = speed
1 h 40 mins = 1 2/3 hours = 5/3 hours
x/(5/3) -(100-x)/(5/3)= 5
3x/5 - 3(100-x)/5 =5
(3x-300+3x)/5 = 5
6x-300=25
6x= 325
x=54.16
one car travels 54.16 miles in 5/3 hours
so in 1 hour it travels 54.16/(5/3)
= 32.5 mph
second car travels 100-54.16 = 45.84 mile
speed = 45.84/(5/3)= 27.5 mph
cheers
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Linear-equations/492700: Find an equation for the line that passes through the given points.
(-5,0) and (1,30) 1 solutions
Answer 335162 by mananth(12270) on 2011-09-07 06:02:28 (Show Source):
You can put this solution on YOUR website!x1 y1 x2 y2
-5 0 1 30
slope m = (y2-y1)/(x2-x1)
( 30 - 0 )/( 1 - -5 )
( 30 / 6 )
m= 5
Plug value of the slope and point (-5 ,0) in
Y = m x + b
0.00 = -25 + b
b= 0 - -25
b= 25
So the equation will be
Y = 5 x + 25
m.ananth@hotmail.ca
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Travel_Word_Problems/492691: a man drove from his home to the airport at a distance of 40 miles and then returned home on the same way. the round trip took 2 hours. his speed on the return trip was 30 miles/hr faster than his speed in going. what was his rate of speed on the trip from his home. 1 solutions
Answer 335152 by mananth(12270) on 2011-09-07 02:07:14 (Show Source):
You can put this solution on YOUR website!Time to airport + time to home = 2hours
d=40
going speed=x
returning speed= x+30
Multiply by the LCD x(x+30)
40(x+30)+40x= 2x(x+30)
40x+1200+40x=2x^2+60x
2x^2-80x+60x-1200=0
2x^2-20x-1200=0
/2
x^2-10x-600=0
(x-30)(x+20)=0
x= 30 the speed while going to airport
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Percentage-and-ratio-word-problems/492615: What quantity of 80 per cent acid solution must be mixed with a 25 percent solution to produce 660 mL of a 50 per cent solution? 1 solutions
Answer 335151 by mananth(12270) on 2011-09-07 01:55:22 (Show Source):
You can put this solution on YOUR website!percent percentage ---------------- quantity
Acid I 80 ---------------- x ml
Acid II 25 ---------------- 660 - x ml
Mixture 50.00% ---------------- 660
80 x + 25 ( 660 - x ) = 50 * 660
80 x + 16500 - 25 x = 33000
80 x - 25 x = 33000 - 16500
55 x = 16500
/ 55
x= 300 ml 80.00% Acid I
360 ml 25.00% Acid II
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Mixture_Word_Problems/492605: Kiera wants to make a solution that is 60% Alcohol. How many liters of a 70% Alcohol solution should Kiera add to 12 liters of a 45% Alcohol solution to achieve her goal? 1 solutions
Answer 335150 by mananth(12270) on 2011-09-07 01:49:29 (Show Source):
You can put this solution on YOUR website!---------------- percent ---------------- quantity
Alcohol I 45 ---------------- 12 liters
Alcohol II 70 ---------------- x liters
Mixture 60 ---------------- 12 + x liters
45 * 12 + 70 x = 60 ( 12 + x )
540 + 70 x = 720 + 60 x
70 x + -60 x = 720 - -540
10 x = 180
/ 10
x = 18
18 liters of 70 % Alcohol
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Linear-equations/492603: line parallel to the line y = 2x + 5 and through the point (2,-3) whats the answer 1 solutions
Answer 335149 by mananth(12270) on 2011-09-07 01:46:04 (Show Source):
You can put this solution on YOUR website!Find the slope of this line
y = 2 x + 5
Divide by 1
y = 2 x + 5
Compare this equation with y=mx+b
slope m = 2
The slope of a line parallel to the above line will be the same
The slope of the required line will be 2
m= 2 ,point (2,-3)
Find b by plugging the values of m & the point in
y=mx+b
-3 = 4.00 + b
b= -7
m= 2
Plug value of the slope and b in y = mx +b
The required equation is y = 2 x -7
y = 2 x -7
m.ananth@hotmail.ca
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Rectangles/492626: a room is 15 feet by 30 feet and the tile 1 foot and cost 92 cent how much will it cost to cover the entire room 1 solutions
Answer 335125 by mananth(12270) on 2011-09-06 23:59:24 (Show Source):
You can put this solution on YOUR website!area of room /area of tile = number of tiles
number of tiles * cost per tile = Total cost of tiling.
15*30 = 450 sq.ft
tile area = 1*1=1 sq.ft
450/1 = 450 tiles
450 *0.92 = $414
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Exponents/492636: Multiply
(-3n)^2(2n^9)^2
I can never remember what to do with exponents like this. Multiply or add? Any help will be greatly appreciated 1 solutions
Answer 335123 by mananth(12270) on 2011-09-06 23:55:15 (Show Source):
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