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Geometry_Word_Problems/331525: The surface area of two cups are in the ratio 9:64 .if the smaller cup has a height of 25 cm and a volume of 2400 cm^3 calculate
a)the height of larger cup.
b)the volume of larger cup.
1 solutions

Answer 237588 by mananth(12270) About Me  on 2010-08-13 02:32:05 (Show Source):
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volume of cylinder = pir^2h
smaller cup
volume = 2400= pi*r^2*25
r^2=2400/(pi*25)
r=sqrt(2400/(pi*25)
r=5.3 cm
..
surface area of smaller cup = 2*pi*r*h
S=2*pi*5.3*25
S= 832.5 sq. cm
..
Ratio of surface area = 9/64
9/64= 832.5/x
x=64*832.5/9
= 5920 sq. cm is the surface area of larger cup


Equations/331504: Find all set of three consecutive even integers whose sum is between 20 and 30.? show your work.
1 solutions

Answer 237587 by mananth(12270) About Me  on 2010-08-13 02:19:14 (Show Source):
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20<3x+6<30
add -6
20-6<3x+6-6<30-6
14<3x<24
divide by3
%2814%2F3%29%3Cx%3C8
..
14/3 = 4.6
even integer between 4.6 & 8 = 6
so the numbers are 6 ,8,10


Numeric_Fractions/331515: WHAT IS THE PRODUCT OF 8 AND T
1 solutions

Answer 237586 by mananth(12270) About Me  on 2010-08-13 01:56:07 (Show Source):


Numbers_Word_Problems/331514: Perimeter of a triangle. The perimeter of a triangle is 195 mm. If the lengths of the sides are consecutive odd integers, find the length of each side.
1 solutions

Answer 237585 by mananth(12270) About Me  on 2010-08-13 01:55:24 (Show Source):
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let the sides be x, x+2,x+4
x+x+2+x+4= 195
3x+6=195
add -6
3x+6-6=195-6
3x=189
divide by 3
x=189/3
x=63
..
The sides are 63 , 65,67 mm


logarithm/331517: log8+log2
1 solutions

Answer 237584 by mananth(12270) About Me  on 2010-08-13 01:51:54 (Show Source):
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log8+log2
log a + log b = log (a*b)
log 8 +log 2 =log(8*2)
=log 16


Linear-equations/331519: Please show me how to find the slope and the y-intercept of the line.
9y+6x+4=17+6x
I'm coming up with a slope of 13/9 and y-intercept is (0,0)
I know that's incorrect.
Please help
1 solutions

Answer 237583 by mananth(12270) About Me  on 2010-08-13 01:46:10 (Show Source):
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9y+6x+4=17+6x
add -6x
9y+6x-6x+4=17+6x-6x
9y=17-4
y=13/9
It is a line parallel to x axis. The line intersects the y axis at 13/9
..
+graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C13%2F9%29


Miscellaneous_Word_Problems/331520: A road is inclined at an angle of 5°. After driving 5000 feet along this road, find the driver's increase in altitude.
1 solutions

Answer 237582 by mananth(12270) About Me  on 2010-08-13 01:38:19 (Show Source):
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inclination = 5 deg
slant travel length = 5000
altitude = ?
..
In a right angled traingle Sin%28theta%29=+altitude+%2F+hypotenuse
Sin%28theta%29%2A+hypotenuse=+altitude
sine5*5000= altitude
0.0872*5000= 436 feet


Geometry_Word_Problems/331493: An American flag has a perimeter of 28ft. Find the dimensions of the flag if the length is 4 ft less than twice its width.
1 solutions

Answer 237570 by mananth(12270) About Me  on 2010-08-12 23:05:36 (Show Source):
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let width be x
length = 2x-4
..
Perimeter = 2*(L+W)
28=2(x+2x-4)
28=6x-8
add 8
28+8=6x+8-8
36=6x
divide by 6
36/6= 6x/6
6=x
width = 6 feet
length = 2x-4
=2*6-4
=12-4
=8 feet


Angles/331495: factor out a factor with a negative coefficient.
-7s-28. (factor completely)
1 solutions

Answer 237568 by mananth(12270) About Me  on 2010-08-12 22:58:48 (Show Source):
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-7s-28
-7(s+4)


Angles/331500: factor completely 27s^4-64s
1 solutions

Answer 237567 by mananth(12270) About Me  on 2010-08-12 22:55:11 (Show Source):
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27s^4-64s
s{(3s)^3-(4)^3}
s{(3s-4)(9s^2+12s+16)}


Polynomials-and-rational-expressions/331468: In a study of worker efficiency at Wong
Laboratories it was found that the number of components
assembled per hour by the average worker t hours after
starting work could be modeled by the formula
N(t)=-3t^3+23t^2+8t
a) Rewrite the formula by factoring the right-hand side
completely.
b) Use the factored version of the formula to find N(3).

1 solutions

Answer 237559 by mananth(12270) About Me  on 2010-08-12 21:47:43 (Show Source):
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N(t)=-3t^3+23t^2+8t
N(t)=-t(3t^2-23t-8)
N(t)=-t((3t^2-24t+t-8))
N(t)=-t(3t(t-8)+1(t-8))
N(t)=-t(3t+1)(t-8)
..
N(3)=-3(9+1)(3-8)
N(3)=150


Expressions-with-variables/331471: How do you write b + c + twice a?
1 solutions

Answer 237556 by mananth(12270) About Me  on 2010-08-12 21:33:37 (Show Source):


Permutations/331470: how do you figure out
3=x^2-4x
1 solutions

Answer 237555 by mananth(12270) About Me  on 2010-08-12 21:33:02 (Show Source):
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x^2-4x-3=0
use the quadratic formula to get the roots of the equation
a=1,b=-4,c=-3
..
x1=-(-4)+sqrt((-4)^2-4*1*(-3)))/2*1
x1=4+sqrt(16+12)/2
x1=4+sqrt28 /2
x1=(4+2sqrt7)/2
x1=2+sqrt7
x2=2-sqrt7


Quadratic_Equations/331210: 16d^2/2d^2-16d+32 multiplied by 2d-8/4d I'm totaly lost on this one.
1 solutions

Answer 237414 by mananth(12270) About Me  on 2010-08-12 09:31:24 (Show Source):
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16d^2/2d^2-16d+32 multiplied by 2d-8/4d
..
16d%5E2%2F2%28d%5E2-8d%2B16%29+%2A+2%28d-4%29%2F4d
..
8d%5E2%2F%28d-4%29%5E2+%2A+%28d-4%29%2F2d
..
4d/(d-4)


Linear-equations/331201: could you please simplify (-2a^6 c^5)^3 over (8a^8 c^17)asap please thanks
1 solutions

Answer 237413 by mananth(12270) About Me  on 2010-08-12 09:25:18 (Show Source):


Travel_Word_Problems/331202: barbara drove 330 miles from home to tuscan on her round trip she was able to increase her speed by 11miles per hour.If the return trip took 1 hour less than find her original speed to tuscan
1 solutions

Answer 237411 by mananth(12270) About Me  on 2010-08-12 09:09:58 (Show Source):
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let the original speed be x mph
on her return it was x+11 mph
..
distance is constant = 330 miles.
..
return was 1 hour less.
time taken while going - time returning = 1 hour
..
time while going = 330/x
time while returning = 330/x+11
..
330/x-330/(x+11)=1
LCD = x(x+11)
330(x+11)-330x/ x (x+11)=1
330x+3630-330x=x(x+11)
3630= x^2 +11x
x^2+11x-3630=0
x^2+66x-55x-3630=0
x(x+66)-55(x+66)=0
(x-55)(x+66)=0
x=55 ignore negative value
original speed = 55 mph


Linear_Equations_And_Systems_Word_Problems/331159: Charles and Paul enter the Center Poin-Comfort Hill Country Run. Charles runs at 8 mi/h and Paul at 6 mi/h. If they start together, how long before charles is 1/4 mi head of Paul?
1 solutions

Answer 237400 by mananth(12270) About Me  on 2010-08-12 06:44:30 (Show Source):
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let x be the distance 1/4 mi ahead of paul.
charles speed = 8mph
paul's speed = 6mph
time taken by both is the same.
time taken by charles = x/8
time taken by paul = x-1/4 / 6
..
x/8= (x-(1/4) /6
x/8=(4x-1)/4*6
x/8= 4x-1/24
24x=8(4x-1)
24x=32x-8
8x =8
x=1 the distance at which charle's is 1/4 mi ahead of paul.
speed of charles = 8 mph
time = distance / speed
time = 1/8 hour
=7.5 minutes. after 7.5 minutes charles will be 1/4 mi ahead of paul


Linear_Equations_And_Systems_Word_Problems/331155: the petty-cash drawer of a small office containing $16.25. If there were twice as many nickels as quarters and as many dimes as nickels and quarters combined, how many coins of each type were there?

1 solutions

Answer 237390 by mananth(12270) About Me  on 2010-08-12 04:45:57 (Show Source):
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let quarters be x
nickels =2x
dimes = (2x+x)
..
Total money = 16.25
25x +5*2x+10*(2x+x)=1625
25x+10x+20x+10x=1625
65x=1625
x= 1625/65
x= 25 the number of quarters
nickels = 2x = 2*25=50
dimes = 3x=3*25=75


Numbers_Word_Problems/331144: i have a number add 8 to my number and the sum is less than twice my number subtract 6 from number and the difference is 1 less than half of my number whats my number
1 solutions

Answer 237387 by mananth(12270) About Me  on 2010-08-12 03:27:00 (Show Source):
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x+8<2x
8<2x-x
8 ;
x-6 x-x/2<6-1
x/2<5
x<10
..
x is greater than 8 & less than 10. so 9 is the number


Miscellaneous_Word_Problems/331149: a mountain resort that featured skiing in the winter was partially staffed by college students in the summer. One summer there were 3 times as many students employed as there were year-round employees. When September came, 40 of the students were back to school and 30 nonstudents were hired for the winter. if there were then twice as many non students as students, how many people staffed the resort in winter?
1 solutions

Answer 237385 by mananth(12270) About Me  on 2010-08-12 03:21:53 (Show Source):
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let employed be x
students be y
y=3x..........................1
..
(y-40)=2(x+30)
y-40 =2x+60
y-2x=60+40
y-2x=100......................2
plug value of y in equation 2
3x-2x=100
x= 100 employed
students = 300


Systems-of-equations/331127: The difference of two numbers is 10. Two times the larger number is 20 more that the smaller. What are the two numbers?
1 solutions

Answer 237384 by mananth(12270) About Me  on 2010-08-12 02:27:17 (Show Source):
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let the bigger number be a
smaller number be b
a-b=10.................1
..
2a=b+20
2a-b=20................2
multiply equation 1 by -1 and add equation 2 to it
-1(a-b)+(2a-b)=-10+20
-a+b+2a-b=10
a=10
plug value of a in equation1
10-b=10
b=0


Age_Word_Problems/331147: Fred is 3 years older than his sister mary. In 7 years she will be six-sevenths of his age. how old are they?
1 solutions

Answer 237383 by mananth(12270) About Me  on 2010-08-12 02:20:20 (Show Source):
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mary's age =x
fred's age will be x+3
..
after 7 years
mary's age = x+7
Fred's age = x+3+7 = x+10
..
x+7= 6/7 * (x+10)
multiply by 7
7(x+7)=(6/7)*7(x+10)
7x+49=6x+60
7x-6x= 60-49
x= 11 years - Mary's age
Fred's age = x+3 = 11+3=14


Linear_Algebra/331145: im a little stuck heres my question:
during one calendar year a state trooper issued a total of 375 citations for warnings and speeding tickets. of these, there were 37 more warnings than speeding tickets. how many warnings and how many speeding tickets were issued?
1 solutions

Answer 237382 by mananth(12270) About Me  on 2010-08-12 02:14:59 (Show Source):
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speeding tickets be x
warning will be x+37
..
x+x+37 = 375
2x+37=375
add-37
2x+37-37=375-37
2x=338
x= 169 speeding tickets
warning= 169+37= 206


Polynomials-and-rational-expressions/331136: Factor the following polynomial 7y + 60 + y^2


1 solutions

Answer 237381 by mananth(12270) About Me  on 2010-08-12 02:10:34 (Show Source):
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y^2+7y+60
..
find roots using quadratic formula
..
x= %28-b%2B-sqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29%29
..
x1= %28-b%2Bsqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29%29
a=1,b=7,c=60
x1= %28-7%2Bsqrt%2849-4%2A1%2A60%29%29%2F%282%2A1%29%29
x1=%28-7%2Bsqrt%28191%29%29%2F2
x2=%28-7-sqrt%28191%29%29%2F2


test/331143: Can you please help me solve this story problem.
Soybean meal is 16% protein. Cornmeal is 8% protein. How many pounds of each should be mixed together in order to get 320 pounds mixture that is 12% protein?
How many pounds of cornmeal should be in the mixture?
How many pounds of the soybean meal should be in the mixture?
Thanks for your help :O)
1 solutions

Answer 237380 by mananth(12270) About Me  on 2010-08-12 02:01:55 (Show Source):
You can put this solution on YOUR website!
Soybean meal is 16% protein. let this be x
Cornmeal is 8% protein. this will be 320-x
320 pounds mixture that is 12% protein?
..
0.16x+0.08(320-x)=320*.12
0.16x+25.6-0.08x=38.4
0.08x=38.4-25.6
0.08x=12.8
x=12.8/0.08
x=160 pounds soyabean
corn will be 160 pounds


test/331134: #1---The length of one leg of a right triangle is 12 meters. the length of the hypotenuse is 8 meters longer than the other leg. find the length of the hypotenuse and the other leg of the triangle.

#2---Two angles are supplementary if the sum of their angles is 180 degrees. One of two supplementary angles is 8 degrees less than three times the other. find the measure of each angle.
1 solutions

Answer 237379 by mananth(12270) About Me  on 2010-08-12 01:53:43 (Show Source):
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#1---The length of one leg of a right triangle is 12 meters. the length of the hypotenuse is 8 meters longer than the other leg. find the length of the hypotenuse and the other leg of the triangle.
let the other leg be x
one leg = 12
hyp = x+8
(x+8)^2=x^2+12^2
x^2+16x+64=x^2+144
16x+64=144
add -64
16x+64-64=144-64
16x=80
x= 5 the other leg.
Hypotenuse = x+8 = 5+8=13

#2---Two angles are supplementary if the sum of their angles is 180 degrees. One of two supplementary angles is 8 degrees less than three times the other. find the measure of each angle.
let one angle be x
the other angle = 3x-8
..
3x-8+x=180
4x-8=180
add 8
4x-8+8=180+8
4x=188
divide by 4
4x/4=188/4
x=47 one angle
second angle = 180 -47=133


Polynomials-and-rational-expressions/331137: Factor the following polynomial 8y - 20 + y^2
1 solutions

Answer 237378 by mananth(12270) About Me  on 2010-08-12 01:46:03 (Show Source):
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8y - 20 + y^2
..
y%5E2%2B8y-20
y%5E2%2B10y-2y-20
%28y%2A%28y%2B10%29-2%2A%28y%2B10%29%29
%28y%2B10%29%2A%28y-2%29


Polynomials-and-rational-expressions/331138: Factor the following polynomial y^3 - 27x^3
1 solutions

Answer 237377 by mananth(12270) About Me  on 2010-08-12 01:42:29 (Show Source):


Geometry_Word_Problems/331139: the measure of the supplement of an angle is 12 degrees greater than three times the measure of a complement. Find the measure of the angle.
180-12 = 3(x) but this does not work. the answer is 51 degrees. I don't know how to get it.
1 solutions

Answer 237376 by mananth(12270) About Me  on 2010-08-12 01:39:49 (Show Source):
You can put this solution on YOUR website!
the measure of the supplement of an angle is 12 degrees greater than three times the measure of a complement. Find the measure of the angle.
..
let angle be x
complement = 90-x
supplement = 180-x
..
180-x=3(90-x)+12
180-x =270-3x+12
add +x
180-x+x=270-3x+x+12
180=-2x+12 +270
add-12
180-12=-2x+12-12
-102=-2x
x=-102/-2
x=51


Miscellaneous_Word_Problems/331142: a store sells 8 more pencils than pens one day. The cost of the pencil is $0.05 and the cost of the pen is $0.20. If the day's sales of pens and pencils equals $8.90, how many pencils were sold.
I know there is something with x + x+8, but I can't figure out what to do with the different prices. Thanks.
1 solutions

Answer 237375 by mananth(12270) About Me  on 2010-08-12 01:31:52 (Show Source):
You can put this solution on YOUR website!
let pens sold be x
pencils sold will be x+8
..
cost of pen = 20 cents
cost of pencils= 5 cents
..
total sales = 890 cents
..
20x+5(x+8)=890
20x+5x+40=890
25x=890-40
25x=850
x=34 pens sold
pencils sold = x+8 = 34+8=42
..
CHECK
34*20+42*5=890


Linear-equations/331121: Simplify please (5y^8z^3)^2(6y^5)
1 solutions

Answer 237367 by mananth(12270) About Me  on 2010-08-11 23:31:29 (Show Source):