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11430..11459 , 11460..11489 , 11490..11519 , 11520..11549 , 11550..11579 , 11580..11609 , 11610..11639 , 11640..11669 , 11670..11699 , 11700..11729 , 11730..11759 , 11760..11789 , 11790..11819 , 11820..11849 , 11850..11879 , 11880..11909 , 11910..11939 , 11940..11969 , 11970..11999 , 12000..12029 , 12030..12059 , 12060..12089 , 12090..12119 , 12120..12149 , 12150..12179 , 12180..12209 , 12210..12239 , 12240..12269 , 12270..12299, >>NextMixture_Word_Problems/441789: Martin needs to mix some 40% alcohol solution with some 90% alcohol solution to obtain 15 liters of an 80% solution. How much of the 40% solution and how much of the 90% solution should he use?
I need the answer quickly, so it would be greatly appreciated if I could receive an answer within a few hours. Thank you very much.
1 solutions
Answer 304822 by mananth(12270)   on 2011-04-28 03:31:34 (Show Source):
You can put this solution on YOUR website! percent ----------------quantity
Alcohol 40 ----------------x
Alcohol 90 ----------------15-x
Total 80.00% ----------------15
40x+90(15-x)=80 *15
40x+1350-90x=1200
40x-90x =1200-1350
-50x=-150
/-50
x=3 liters 40.00%
12 liters 90.00%
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Travel_Word_Problems/441791: Anna & John both travel to their new home 400 miles away. Anna drive at avrg speed of 60mph. where as John at 50mph. during journey Anna stops over for 1h.20 min and john stops half as long .what is the difference in minutes between their arrival time ??
1 solutions
Answer 304820 by mananth(12270) on 2011-04-28 03:26:08 (Show Source):
You can put this solution on YOUR website!Anna speed = 60 mph
so she will take 400/60
=6 hours 40 minutes without a halt
She halts for 1hour 20 hours
So she takes 8 hours
...
John speed = 50 mph.
So he takes 400/50 = 8 hours without halt.
he halts for 40 minutes
so he takes 8 hours 40 minutes to reach
difference 40 minutes
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Miscellaneous_Word_Problems/441209: Bayside insurance offers two health plans. Under plan A, Giselle would have to pay the first $160 of her medical bills, plus 25% of the rest. Under plan B, Giselle would pay the first $240, but only 20% of the rest, for what amount of medial bills will plan B save Giselle money? Assume she has over $240 in bills
1 solutions
Answer 304577 by mananth(12270) on 2011-04-27 09:08:30 (Show Source):
You can put this solution on YOUR website!let the bill amount be x
Plan A= 160 + 25.00% of rest
Plan B= 240 + 20.00% of the rest
Plan B < Plan A
240+0.25(x-240)<160+0.25(x-160 )
240+0.20x-60<160+0.25x-40
240-160 -60+40 <0.25x-0.2x
60<0.05 x
1200 < x
X > 1200 for plan B to save money
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Numbers_Word_Problems/441228: The sum of two numbers is 50. Two times the first number is ten more than the second. Find the two numbers.
1 solutions
Answer 304576 by mananth(12270) on 2011-04-27 09:02:34 (Show Source):
You can put this solution on YOUR website!let one number be x & the other y
1 x + 1 y = 50 .............1
2 x + -1 y = 10 .............2
Add the two equations
3 x = 60
/ 3
x = 20
plug value of x in (1)
1 x + 1 y = 50
20 + 1 y = 50
1 y = 50 -20
1 y = 30
y = 30
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Graphs/440722: Could someone please help me to graph the line containing the given pair of points and find the slope?
(6, 3) (-5, -2)
1 solutions
Answer 304358 by mananth(12270) on 2011-04-26 09:14:21 (Show Source):
You can put this solution on YOUR website!x1 y1 x2 y2
6 3 -5 -2
slope m = (y2-y1)/(x2-x1) 0.45
m= 0.45
Plug value of the slope and point (6,3)in
Y =mx+b
3.00=2.73+b
b=3-2.73
b=0.27
So the equation will be
Y =0.45x+0.27
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Evaluation_Word_Problems/440728: Hello,
I need help on two problems using the substitution method;
The solution to the system of equation below is (8,4)
3x-5y
7x + 3y = 68
The second problem is:
Bill invested some money at 5% annual interest, and Jeanette invested some at 7%. If their combined interest was $310 on a total investment of $5,000, how much did Bill invest?
Thanks in advance
1 solutions
Answer 304355 by mananth(12270) on 2011-04-26 09:05:38 (Show Source):
You can put this solution on YOUR website!Bill 5.00% per annum
Jeanette 7.00% per annum
x+y=5000 ------------------------1
5.00%x+7.00%y=$310.00
Multiply by 100
5x+7y=$31,000.00 --------2
Multiply (1) by -5
we get
-5x-5y= -25000.00
Add this to (2)
2y=$6,000.00
divide by 2
y= $3,000.00 investment at 7.00%---- Jeanette
Balance $2,000.00 investment at 5.00% --- Bill
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Travel_Word_Problems/440674: two cars leave an intersection. One car travela north the other east. When the car traveling north had gone 9 mi, the distance between the cars was 3 mi more than the distance traveled by the car heading east. How far had the eastbond car travled?
1 solutions
Answer 304336 by mananth(12270) on 2011-04-26 02:17:47 (Show Source):
You can put this solution on YOUR website!let east bound car travel x miles
North bound - 9 miles
At right angles
Use pythagoras theorem
x^2++9^2=(x+3)^2
x^2+81=x^2+6x+9
6x=72
x=12
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Linear_Algebra/440647: pls.solve it! 4x-3y=-4,10x+y=7
Thank you!!!
nove_1990@yahoo.com
1 solutions
Answer 304329 by mananth(12270) on 2011-04-25 23:35:06 (Show Source):
You can put this solution on YOUR website!4x-3y=-4 .............1
10x+y=7 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by 3
4x-3y= -4
30x+3y= 21
Add the two equations
34x= 17
/34
x=0.50
plug value of x in (1)
4x-3y=-4
2-3y=-4
-3y=-4-2
-3y=-6
y=2
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Matrices-and-determiminant/439710: Kate borrows $10,000. Some is from her friend at 8% annual
interest, twice as much as that from her bank at 9%, and the remainder
from her insurance company at 5%. She pays a total of $830 in interest
for the first year. How much did she borrow from each source?
1 solutions
Answer 303899 by mananth(12270) on 2011-04-24 05:58:19 (Show Source):
You can put this solution on YOUR website!friend ----------- x-------------8%
Bank--------------2x-------------9%
Insurance company---10,000-3x----5%
8x+9*2x+5(10000-3x)=830*100
8x+18x+50000-15x=83000
11x=83000-50000
11x=33000
/11
x==3000 from friend
Bank ---2x= 6000
insurance = 1000
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Miscellaneous_Word_Problems/439716: the sum of two numbers is twenty five. twice the larger number is equal to three times the smaller one. find the two numbers.
1 solutions
Answer 303896 by mananth(12270) on 2011-04-24 05:42:21 (Show Source):
You can put this solution on YOUR website!x+y=25...................1
2x=3y
2x-3y=0..................2
Eliminate y
multiply (1)by 3
Multiply (2) by 1
3 x + 3 y = 75
2 x + -3 y = 0
Add the two equations
5 x = 75
/ 5
x = 15
plug value of x in (1)
1 x + 1 y = 25
15 + 1 y = 25
1 y = 25-15
1 y = 10
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Miscellaneous_Word_Problems/439717: one apple and five oranges cost twenty nine rupees while three apples and four oranges cost thirty two rupees. find the total cost of four apples and five oranges.
1 solutions
Answer 303895 by mananth(12270) on 2011-04-24 05:38:55 (Show Source):
You can put this solution on YOUR website!Apple ----------x
Orenge ------------ y
1 x + 5 y = 29 .............1
3 x + 4 y = 32 .............2
Eliminate y
multiply (1)by -4
Multiply (2) by 5
-4 x -20 y = -116
15 x 20 y = 160
Add the two equations
11 x = 44
/ 11
x = Rs 4.00 Apple
plug value of x in (1)
1 x + 5 y = 29
4 + 5 y = 29
5 y = 29 -4
5 y = 25
y = Rs 5.00 Orange
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Mixture_Word_Problems/439343: What quantity of 80 per cent acid solution must be mixed with a 30 per cent solution to produce 1050 mL of a 50 per cent solution?
mL of acid solution =
1 solutions
Answer 303682 by mananth(12270) on 2011-04-22 23:47:29 (Show Source):
You can put this solution on YOUR website! percent ---------------- quantity
Acid I 80 ---------------- x
Acid II 30 ---------------- 1050 - x
Total 50.00% ---------------- 1050
80x+30(1050-x)= 50*1050
80x+31500-30x=52500
80x-30x =52500-31500
50x=21000
/50
x=420 ml 80.00%
630 ml 30.00%
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Finance/439388: Bayside insurance offers two health plans. Under plan a, Giselle would have to pay the first $70 of her medical bills, plus 35% of the rest. Under plan b, Giselle would have to pay the first $230 and 30% for of the rest. For what amount of medical bills will plan b save Giselle money?
1 solutions
Answer 303679 by mananth(12270) on 2011-04-22 23:41:20 (Show Source):
You can put this solution on YOUR website!let the bill amount be x
Plan A= 75 + 35.00% of rest
Plan B= 230 + 30.00% of the rest
Plan B < Plan A
230+0.35(x-230)<75+0.35*x
230+0.30x-80.5<75+0.35x-26.25
230-75-80.5+26.25<0.35x-0.3x
100.75<0.05x
2015
the bill should be greater than $2015
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Linear_Equations_And_Systems_Word_Problems/439419: A swimming pool holds 540,000 liters of water. THe pool has two drainage pipes. When the pool is completely full, the first pipe alone can empty it in 180 min, and the second pipe alone can empty it in 120 min. When both pipes are draining together, how long does it take them to empty the pool?
1 solutions
Answer 303674 by mananth(12270) on 2011-04-22 23:18:54 (Show Source):
You can put this solution on YOUR website!Pipe A 3 hours
It does 1/ 3 of the job in 1 hour
Pipe B 2 hours
It does 1/ 2 of thejob in 1 hour
Together they will do 1/ 3 + 1/ 2
Together they will do 5/ 6 of the job in one hour
So they will take 1 1/5 hours
So they will take 1.2 hours = 72 minutes
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Money_Word_Problems/437643: A woman earns $900 in interest from two accounts in a year. If she has three times as much invested at 8% as she does at 6%, how much does she have in each account?
1 solutions
Answer 302784 by mananth(12270) on 2011-04-19 02:16:46 (Show Source):
You can put this solution on YOUR website!Part I 6.00% per annum -------------x
Part II 8.00% per annum ------------y=3x
total investment
Interest----- $900.00
6.00% x + 8.00% * 3 x = $900.00
0.06 x + 0.08 * 3 x = $900.00
0.06 x + 0.24 x = $900.00
0.3 x = $900.00
/ 0.3
x= $3,000.00 --- Part I
3x=$9,000.00 Part II
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Word_Problems_With_Coins/437670: The bill for 5 glasses of apple juice and 4 salads is $9.50,but the bill for 4 glasses of apple juice and 5 salads is $ 10.30. What would be the bill for a glass of juice and a salad?
1 solutions
Answer 302782 by mananth(12270) on 2011-04-19 02:10:57 (Show Source):
You can put this solution on YOUR website!Apple juice cost x
Salad cost ------------ y
5x+4y=9.5 .............1
4x+5y=10.3 .............2
Eliminate y
multiply (1)by -5
Multiply (2) by 4
-25x-20 y=-47.5
16x+20y =41.2
Add the two equations
-9x=-6.3
/-9
x=0.70
plug value of x in (1)
5x+4y=9.5
3.5+4y=9.5
4y=9.5-3.5
4y=6
y=1.50
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Linear-equations/437699: solve for subsitution
15x-10y=1
15y=2+5x
8x+5y+14
x=52-9y
solve equation by graphong
x+y=4
y-x=4
solve by elimination
8x-y=47
x+y=16
1 solutions
Answer 302781 by mananth(12270) on 2011-04-19 02:02:40 (Show Source):
You can put this solution on YOUR website!15x-10y=1.............1
15y=2+5x ---------2
/15
y=0.13+ 0.33x
Plug the value of y in (1)
15x-10(0.13+0.33x)=1
15x-1.33-3.33x=1
15x-3.33x=1+1.33
11.67x=2.33
/11.67
x=0.2
Plug the value of x in (1)
15x-10y =1
15*0.2-10y=1
3-10y=1
-10y=-2
/-10
y=0.2
.......................
8x+5y=14 .............1
9y=52-x ---------2
/9
y=5.78-0.11x
Plug the value of y in (1)
8x+5(5.78-0.11x)=14
8x+28.89-0.56x=14
8x-0.56x=14-28.89
7.44x=-14.89
/7.44
x=-2
Plug the value of x in (1)
8x+5y=14
8*-2+5y=14
-16+5y=14
5y=30
/5
y=6
..................................
x+y=4 .............1
-x+y =4 .............2
Eliminate y
multiply (1)by -1
Multiply (2) by 1
-x-y=-4
-x+y=4
Add the two equations
-2x = 0
x=0
plug value of x in (1)
x+y=4
y=4
equation1
when x= 0 y=4(0,4)
when y =0,x=4(4,0)
Equation 2
when x= 0,y=4(0,4)
when y =0x=-4(-4,0)
...
................
8 x + -1 y = 47 .............1
1 x + 1 y = 16 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by 1
8 x -1 y = 47
1 x 1 y = 16
Add the two equations
9 x = 63
/ 9
x = 7
plug value of x in (1)
8 x + -1 y = 47
56 + -1 y = 47
-1 y = 47 -56
-1 y = -9
y = 9
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Age_Word_Problems/437671: Cory's age is 20% of her father's age. Forty-two years from now, Cory's age will be two-thirds (2/3) of her father's age. How old are Cory and her father now?
1 solutions
Answer 302773 by mananth(12270) on 2011-04-18 23:47:20 (Show Source):
You can put this solution on YOUR website!cory's age = 20% of father's age
so father is 5 times cory's age
let cory's age = x
father's age = 5x
42 years later
Cory's age x+42
father's age 5x+42
If Cory 's age = 2/3 of father's age then father is 1.5 times cory's age
father's age 1.5 times older
5x+42=1.5(x+42)
5x+42=1.5x+63
3.5x=63 -42
3.5x=21
/3.5
x=6 Cory's age
x+20=26 years father's age
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Triangles/437674: In a right triangle, if one acute angle has measure 6x-10 and the other has measure 2x-4 , find the larger of these two angles
1 solutions
Answer 302772 by mananth(12270) on 2011-04-18 23:39:28 (Show Source):
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Travel_Word_Problems/437560: Sarah hikes at 4 kilometers per hour from one end of a trail that is 34 km long. Amanda begins 1 hr laater at the other end. Walks toward sarah at 6 k/m. How long will it take for them to pass each other
1 solutions
Answer 302737 by mananth(12270) on 2011-04-18 21:17:06 (Show Source):
You can put this solution on YOUR website!Sarah 4 km/h
Amanda 6 km/h 1 hours late
Distance 37 km
1hour Sarah has traveled 4 km before Amanda starts
So distance = 33 When amanda starts
Let time they take to meet be x hours
Sarah distance traveled 4 x miles
Amanda distance traveled 6 x miles
Time taken to meet is same
t=d/r
combined speed= 10 km/h
10 x = 33 2.44
x= 3.3 hours after Amanda starts
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Miscellaneous_Word_Problems/437600: how many gallons of a 50% antifreeze solution must be mixed with 60 gallons of 20% antifreeze to get a mixture that is 40% antifreeze
1 solutions
Answer 302726 by mananth(12270) on 2011-04-18 20:59:31 (Show Source):
You can put this solution on YOUR website!------ Percent ---------------- quantity
Antifreeze 20 ---------------- 60
Antifreeze 50 ---------------- x
Total 40 ---------------- 60 + x
20*60+50*x=40(60+x)
1200+50x=2400+40x
50x-40x=2400-1200
10x=1200
/10
x=120 gallons 50 % Antifreeze
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Percentage-and-ratio-word-problems/437599: how many gallons of a 90% antifreeze solution must be mixed with 90 gallons of 15% antifreeze to get a mixture that is 80% antifreeze?
1 solutions
Answer 302724 by mananth(12270) on 2011-04-18 20:54:09 (Show Source):
You can put this solution on YOUR website!------ Percent ---------------- quantity
Antifreeze 15 ----------------90
Antifreeze 90 ----------------x
Total 80 ---------------- 90 + x
15*90+90*x=80(90+x)
1350+90x=7200+80x
90x-80x =7200-1350
10x=5850
/10
x=585 gallons 90 % Antifreeze
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Travel_Word_Problems/437587: a plane flys 420 miles with the wind and 350 miles against the wind at the same length of time with a wind speed of 20 miles per hour what is the speed of the plane
1 solutions
Answer 302714 by mananth(12270) on 2011-04-18 20:44:18 (Show Source):
You can put this solution on YOUR website!plane speed x mph
wind speed 20 mph
..
against wind x-20 mph
with wind x+20 mph
Distance against wind 350
Distance with tail wind 420
Time = same
350/(x- 20)=420/(x+20)
350*(x+20)=420*(x-20)
350x+7000=420x -8400
420x-350x=8400+ 7000
70x=15400
/70
x= 220 mph
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Travel_Word_Problems/437577: Flying against a headwind, a plane covers 900 miles in 2 hours. The return trip with a tailwind only takes an hour and a half. Find the speed of the wind, and the speed of the plane within the air mass.
1 solutions
Answer 302707 by mananth(12270) on 2011-04-18 20:39:25 (Show Source):
You can put this solution on YOUR website!against wind 2.00 hours
with wind 1.50 hours
Distance = same=900
plane speed =x
wind speed =y
t=d/r
900/(x-y)=2.00
2(x-y)= 900.00
2x-2y=900 ....................1
900/(x+y)=1.50
1.50(x+ y)=900
1.50x+1.50y=900 ...............2
Multiply (1) by 1.50
Multiply (2) by 2.00
we get
3x-3y=1350
3x+3y=1800
6x=3150
/6
x=525mph plane speed
plug value of x in (1)
2x-2y=900
1050-2y =900
-2y=900-1050
-2y=-150
y=75 mph wind speed
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test/437259: Solve. A boat moves 5 kilometers upstream in the same amount of time it moves 17 kilometers downstream. If the rate of the current is 8 kilometers per hour, find the rate of the boat in still water.
A. 7 1/12 kilometers per hour
B. 3 1/3 kilometers per hour
C. 8 kilometers per hour
D. 14 2/3 kilometers per hour
1 solutions
Answer 302450 by mananth(12270) on 2011-04-18 09:13:07 (Show Source):
You can put this solution on YOUR website!Boat speed x mph
current speed 8 mph
..
against current x- x - 8 mph
with current x+ x + 8 mph
Distance against wind 5
Distance with tail wind 17
Time = same
5 /(x- 8 )= 17 /(x+ 8 )
5 *(x+ 8 )= 17 *(x- 8 )
5 x + 40 = 17 x -136
17 x -5 x = 136 + 40
12 x = 176
/ 12
x= 14.67 mph
option D
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test/437276: Write an equation in point slope form of the line that passes through the given points ( -3, 1/2) ; (-7,5/2)
1 solutions
Answer 302448 by mananth(12270) on 2011-04-18 09:02:45 (Show Source):
You can put this solution on YOUR website!x1 y1 x2 y2
-3 0.5 -7 2.5
slope m = (y2-y1)/(x2-x1) -0.5
m= -0.5
Plug value of the slope and point ( -3 , 0.5 ) in
Y = m x + b
0.50 = 1.5 + b
b= 0.5 1.5
b= -1
So the equation will be
Y = -0.5 x + -1
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