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1 solutions
Answer 333350 by ankor@dixie-net.com(15746)   on 2011-08-30 14:42:46 (Show Source):
You can put this solution on YOUR website!a man rides up a ski lift at the rate of 5 miles an hour and skis back down the hill at the rate of 50 miles an hour.
if the complete trip requires 22 minutes, how far is it from the bottom to the top of the hill?
:
Assuming the distance up is equal to the distance down.
let d = the one-way distance
:
Change 22 min to  =  hr
:
Write a time equation: time = dist/speed
:
time up + time down = 22 min
 +  =
multiply equation by 150, results
30d + 3d = 5(11)
33d = 55
d = 
d = 1  mi from the bottom to the top of the hill
:
:
Check this: Find the actual times each way, Use 1.67 mi dist and .367 hrs as the time (22/60)
:
1.67/5 = .333 hrs
1.67/50 =.033 hrs
--------------------
total time: .366 hrs which ~ 22 min
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Word_Problems_With_Coins/487830: Marie poured her coins into a machine. The machine counted 88 coins. For every penny, there were 5 nickles, 3 dimes, and 2 quaters. What was the total value of maries coins?
1 solutions
Answer 333262 by ankor@dixie-net.com(15746) on 2011-08-29 22:02:08 (Show Source):
You can put this solution on YOUR website!Marie poured her coins into a machine. The machine counted 88 coins.
For every penny, there were 5 nickles, 3 dimes, and 2 quarters.
What was the total value of maries coins?
:
let x = no. of pennies
then
5x = no. of nickels
3x = no. of dimes
2x = no. of quarters
:
Find x
x + 5x + 3x + 2x = 88
11x = 88
x = 88/11
x = 8 pennies
then we have
40 nickels
24 dimes
16 quarters
Find the value
.01(8) + .05(40) + .10(24) + .25(16) = $
:
I have to exit right now, You should be able to finish this now. C
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Rate-of-work-word-problems/487686: If Jan can weed the garden in 2 hours and her husband can weed it in 1 hour and 30 minutes, find how long it takes them to weed the garden together.
1 solutions
Answer 333223 by ankor@dixie-net.com(15746) on 2011-08-29 19:04:34 (Show Source):
You can put this solution on YOUR website!If Jan can weed the garden in 2 hours and her husband can weed it in 1 hour and 30 minutes, find how long it takes them to weed the garden together.
:
Let t = time required when weeding together
Let the completed job = 1 (a weed-free garden)
:
 +  = 1
we can clear the denominators by multiplying by 6, results:
3t + 4t = 6
7t = 6
t =  hrs working together, that's *60 = 51.43 minutes
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Travel_Word_Problems/487683: To reach city A, you travel north for 2.00 hours covering 80.0 miles. You then turn due east and travel 45.0 minutes for another 20.0 miles to reach your destination. On the first leg of your trip (traveling north), what is your speed?
1 solutions
Answer 333221 by ankor@dixie-net.com(15746) on 2011-08-29 18:55:19 (Show Source):
You can put this solution on YOUR website!To reach city A, you travel north for 2.00 hours covering 80.0 miles.
On the first leg of your trip (traveling north), what is your speed?
:
That's easy; 80 mi in 2hr, obviously you are going 40 mph
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Rectangles/487624: The length of a rectangle is increased by 60% By what percent would the width have to be decreased to maintain the same area?
1 solutions
Answer 333186 by ankor@dixie-net.com(15746) on 2011-08-29 17:17:17 (Show Source):
You can put this solution on YOUR website!The length of a rectangle is increased by 60% By what percent would the width have to be decreased to maintain the same area?
:
let x = the decimal equiv decrease of the width
:
Write an area equation
Original area = new area
L * W = 1.6L * xW
Divide both sides by LW
1 = 1.6 * x
divide both sides by 1.6
 = x
x = .625,
new width = .625*old width, therefore
1 - .625 = .375 * 100 = 37.5 decrease in the width to have the same area
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Word_Problems_With_Coins/487828: If there is $1.60 in change and you have the same amount of dimes, nickels, and quarters then how many coins are there?
1 solutions
Answer 333180 by ankor@dixie-net.com(15746) on 2011-08-29 17:04:35 (Show Source):
You can put this solution on YOUR website!If there is $1.60 in change and you have the same amount of dimes, nickels, and quarters
then how many coins are there?
:
Let x = the number of each coin
:
.05x + .10x + .25x = 1.60
.40x = 1.60
x = 
x = 4 of each coin, therefore there are 3(4) 12 coins in all
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Travel_Word_Problems/487869: Jack travels from A to B at 30 mph, and returns at 10 mph. Jill leaves at the same time as Jack, and travels from A to B and back at a constant speed of 20 mph. Who gets back first?
1 solutions
Answer 333176 by ankor@dixie-net.com(15746) on 2011-08-29 16:57:16 (Show Source):
You can put this solution on YOUR website!Jack travels from A to B at 30 mph, and returns at 10 mph.
Jill leaves at the same time as Jack, and travels from A to B and back at a constant speed of 20 mph.
Who gets back first?
:
let d = the one way distance
let a = Jack's average speed for the round trip
:
write a time equation
 +  = 
Multiply by 30a
da + 3da = 30(2d)
da + 3da = 60d
Simplify divide by d
a + 3a = 60
4a = 60
a = 
a = 15 mph av speed, obviously, Jill will get back first
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Linear-equations/487728: 24.
a = 1 + b,
b = 5 − 2a
Thanks for any help.
1 solutions
Answer 333172 by ankor@dixie-net.com(15746) on 2011-08-29 16:43:19 (Show Source):
You can put this solution on YOUR website!a = 1 + b,
b = 5 − 2a
Using the 1st equation, we can replace a with (1+b) in the 2nd equation
b = 5 - 2(1+b)
b = 5 - 2 - 2b
b + 2b = 5 - 2
3b = 3
b = 1
:
Find a using the 1st equation, replace b with
a = 1 + 1
a = 2
:
:
Check these solutions in the 2nd equation b = 5 - 2a
1 = 5 - 2(2)
1 = 5 - 4
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Age_Word_Problems/487722: two years back a father was 3 times as old as his son.two years hence, twice the fathers age will equal to 5 times that of his son's age.what are their present ages?
1 solutions
Answer 333162 by ankor@dixie-net.com(15746) on 2011-08-29 16:16:30 (Show Source):
You can put this solution on YOUR website!let f = father's present age
let s = son's present age
:
Write an equation and simplify it, for each statement
:
"two years back a father was 3 times as old as his son."
f - 2 = 3(s - 2)
f - 2 = 3s - 6
f = 3s - 6 + 2
f = 3s - 4
:
"two years hence, twice the fathers age will equal to 5 times that of his son's age."
2(f + 2) = 5(s + 2)
2f + 4 = 5s + 10
2f = 5s + 10 - 4
2f = 5s + 6
:
From the 1st equation we know f = (3s-4), replace f in the above equation
2(3s - 4) = 5s + 6
6s - 8 = 5s + 6
6s - 5s = 6 + 8
s = 14 yrs is son's present age
then
f = 3(14) - 4
f = 42 - 4
f = 38 yrs is father's present age
;
:
See if this works in the statement:
"two years hence, twice the fathers age will equal to 5 times that of his son's age."
2(38+2) = 5(14+2)
2(40) = 5(16); confirms our solutions of f=38 and s=14
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Age_Word_Problems/487851: A 37 year old father has a 4 year old son. In how many years will the father be exactly 4 times as old as his son.
1 solutions
Answer 333159 by ankor@dixie-net.com(15746) on 2011-08-29 16:06:04 (Show Source):
You can put this solution on YOUR website!A 37 year old father has a 4 year old son.
In how many years will the father be exactly 4 times as old as his son.
:
Let y = no. of years until this is true
:
y + 37 = 4(y + 4)
y + 37 = 4y + 16
37 - 16 = 4y - y
21 = 3y
y = 
y = 7 years
:
:
You can confirm this: 37 + 7 = 4(7 + 4)
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Linear-equations/487835: Two ships leave port at the same time. Ship A sails north at a speed of 10 mph while ship B sails east at a speed of 35 mph. Find an expression in terms of the time t (in hours) giving the distance between two ships.
1 solutions
Answer 333148 by ankor@dixie-net.com(15746) on 2011-08-29 15:35:36 (Show Source):
You can put this solution on YOUR website!Two ships leave port at the same time. Ship A sails north at a speed of 10 mph while ship B sails east at a speed of 35 mph.
Find an expression in terms of the time t (in hours) giving the distance between two ships.
:
This is a right triangle problem, c^2 = a^2 + b^2
where
c = is the distance between the ship after t hrs
a = 10t
b = 35t
:
Dist = 
|
Average/487833: If i have a 88 average and make a 62 on my final which is worth 30% of my grade what is my final grade
1 solutions
Answer 333147 by ankor@dixie-net.com(15746) on 2011-08-29 15:25:52 (Show Source):
You can put this solution on YOUR website!If i have a 88 average and make a 62 on my final which is worth 30% of my grade
what is my final grade
:
Ratio of grades to final: 7:3
;
fg = 
:
fg = 
:
fg = 
fg = 80.2 is the final grade
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Numbers_Word_Problems/487726: four times the sum of a number and 2 is same as 10 less than the number. find the number. thank you its very important
1 solutions
Answer 333146 by ankor@dixie-net.com(15746) on 2011-08-29 15:19:21 (Show Source):
You can put this solution on YOUR website!Let n = "the number"
:
just write what it says:
four times the sum of a number and 2 is same as 10 less than the number.
4(n+2) = n - 10
4n + 8 = n - 10
4n - n = -10 - 8
3n = -18
n = 
n = -6
:
:
See if that works in the original statement:
"four times the sum of a number and 2 is same as 10 less than the number. "
4(-6+2) = -6 - 10
4(-4) = -16; confirms our solution of n=-6
:
:
:
That's was pretty easy, wasn't it?
|
Expressions-with-variables/487670: I'm trying to solve an algebra problem and the examples in the book are very confusing.
I need to use the substitution method.
x-y=5
x+2y=7
If you could just show me the work to reach the solution, I think I can do the rest of the problem?
1 solutions
Answer 333100 by ankor@dixie-net.com(15746) on 2011-08-29 08:23:57 (Show Source):
You can put this solution on YOUR website!use the substitution method.
x - y = 5
x + 2y = 7
Choose which equation you are going to use to substitute, we will choose the 1st one
x - y = 5
add y to both sides
x = (y + 5)
:
now on the 2nd equation we can substitute (y+5) for x
x + 2y = 7
substitute
(y+5) + 2y = 7
subtract 5 from both sides
y + 2y = 7 - 5
3y = 2
Divide both sides by 3
y =
:
Find x:
we know that x = y + 5
x = + 5
x = 5
:
Check solutions in the 2nd equation
x + 2y = 7
5 + 2( ) = 7
5 +  = 7
5 + 1  = 7; confirms our solution
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Numbers_Word_Problems/487316: the sum of three integers is 232. the sum of the first and second integers exceeds the third by 92. the third integer is 48 less than the first. find the three integers
1 solutions
Answer 333070 by ankor@dixie-net.com(15746) on 2011-08-28 22:16:31 (Show Source):
You can put this solution on YOUR website!the sum of three integers is 232.
a + b + c = 232
:
the sum of the first and second integers exceeds the third by 92.
a + b = c + 92
a + b - c = 92
:
the third integer is 48 less than the first.
c = a - 48
:
The first and 2nd equations for elimination
a + b + c = 232
a + b - c = 92
----------------subtraction eliminates a and b, find c
2c = 140
c = 70, the 3rd digit
:
The third equation
a - 48 = 70
a = 70 + 48
a = 118, the first digit
:
Find the 2nd digit
118 + b = 70 + 92
b = 162 - 118
b = 44, the 2nd digit
:
:
Check: 118 + 44 + 70 = 232
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Travel_Word_Problems/487422: Carlos and Maria drove a total of 24 miles in 4.9 hours. Carlos drove the first part of the trip and averaged 54 mph. Maria drove the remainder of the trip and averaged 47 mph. For approximately how many hours did Maria drive/ Thanks for your help.
1 solutions
Answer 333067 by ankor@dixie-net.com(15746) on 2011-08-28 21:18:14 (Show Source):
You can put this solution on YOUR website!Carlos and Maria drove a total of 24 miles in 4.9 hours.
Carlos drove the first part of the trip and averaged 54 mph.
Maria drove the remainder of the trip and averaged 47 mph.
For approximately how many hours did Maria drive/
:
24 miles in 4.9 hrs does not make sense, that's about the speed you would walk.
Let's assume it's 240 miles, that would be reasonable
:
let m = M's drive time
the total time was given as 4.9 hrs, therefore
(4.9-m) = C's drive time
:
Write a distance equation, dist = speed * time
:
M's dist + C's dist = 240
47m + 54(4.9-m) = 240
47m + 264.6 - 54m = 240
47m - 54m = 240 - 264.6
-7m = -24.6
m = 
m ~ +3.5 hrs driven by M
;
:
Check this by finding the distances (C drives 4.9 - 3.5 = 1.4 hrs)
54*1.4 = 75.6 mi
47*3.5 = 164.5 mi
---------------
total dist:241 ~ 240
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Mixture_Word_Problems/487281: This is actually a real-life situation. I'm trying to mix 90% alcohol with 50% alcohol so that I get a solution of at least 70%.
(the 50% is a wintergreen that helps the whole thing smell less clinical.)
I am a band director who did very poorly in math many years ago, and am trying to mix a solution of alcohol in order to disinfect mouthpieces that multiple kids will play on as they try instruments.
1 solutions
Answer 333066 by ankor@dixie-net.com(15746) on 2011-08-28 20:53:47 (Show Source):
You can put this solution on YOUR website!mix 90% alcohol with 50% alcohol so that I get a solution of at least 70%.
:
You must decide how much of the resulting solution you want
As an example, let's say you want 10 quarts of the 70% solution
:
Let x = amt of 90% alcohol required
then
(10-x) = amt of 50% alcohol required
:
A mixture equation
.90x + .50(10-x) = .70(10)
.9x + 5 - .5x = 7
.9x - .5x = 7 - 5
.4x = 2
x = 
x = 5 quarts
so this works very easily; 5 qt of each will give a 70%
:
From this you can say, mix equal amts of the two
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Travel_Word_Problems/487486: You drive a car 3 h at 48 km/h, then 3 h at 67 km/h.
What is your average velocity?
1 solutions
Answer 333065 by ankor@dixie-net.com(15746) on 2011-08-28 20:44:19 (Show Source):
You can put this solution on YOUR website!You drive a car 3 h at 48 km/h, then 3 h at 67 km/h.
What is your average velocity?
:
Let a = your average velocity of the trip
:
Write a distance equation
:
total dist = 48km/hr dist + 67km/hr dist
6a = 3(48) + 3(67)
6a = 144 + 201
6a = 345
a = 
a = 57.5 km/hr average
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Travel_Word_Problems/486932: Lafe is in his 4*4 300 miles due east of a car driven by shannell and is traveling due west at 30 mph. Shannell is speeding at 60 mph due north. At what time are they closest to each other.
I know this one is a minimizing problem and i tried to draw a picture of the situation but it is not making much sense.
1 solutions
Answer 333061 by ankor@dixie-net.com(15746) on 2011-08-28 20:32:47 (Show Source):
You can put this solution on YOUR website!Lafe is in his 4*4 300 miles due east of a car driven by shannell and is traveling due west at 30 mph.
Shannell is speeding at 60 mph due north.
At what time are they closest to each other.
:
let x = travel time of both vehicles
:
This is right triangle problem c =  , where
c = distance between the cars
a = 60t, 4by4 travel distance
b = (300-30t) travel distance from a point due south of the 4by4
:
The easiest way to solve this enter/plot this equation in your Ti83 or equiv
y = 
looks like this
:
where distance between the cars are on the y axis and the time in hrs on the x axis. Actual minimum (from my Ti83) x = 2 hrs, y ~ 268 mi
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Linear_Equations_And_Systems_Word_Problems/486830: Samuel has an alloy containing 11% gold. Taylor has 1/2 ounces of an alloy containing 70% gold. They combined their alloys to make an alloy with 36 2/7% gold. Gold is worth $388.31 an ounce at the current market value. Samuel estimated the value of the new alloy to be $164.38 an ounce. How many ounces of Samuel's alloy were used?
1 solutions
Answer 333044 by ankor@dixie-net.com(15746) on 2011-08-28 19:02:10 (Show Source):
You can put this solution on YOUR website!Samuel has an alloy containing 11% gold.
Taylor has 1/2 ounces of an alloy containing 70% gold.
They combined their alloys to make an alloy with 36 2/7% gold.
Gold is worth $388.31 an ounce at the current market value.
Samuel estimated the value of the new alloy to be $164.38 an ounce.
How many ounces of Samuel's alloy were used
:
Change 36  to 36.2857%
:
Let x = amt of Sam's alloy used
:
.11x + .70(.5) = .362857(x+.5)
:
.11x + .35 = .362857x + .18143
:
.35 - .18143 = .362857x - .11x
:
.16857 = .252857x
x = 
x = .667 oz of 11% alloy
:
Check this using the values given
.362857(.6667+.5) = .4233 oz of gold
Find the value
.4233 * 388.31 = $164.37, which is within 1 cent
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Quadratic_Equations/487150: We are trying to Factor the equation 2x^4 - 4x^3 + 8x^2. We factor out 2x^2 out. 2x^2(x^2 - 2x + 4) We then input into the quadratic equation (-(-2) +/- sqroot of -2^2 - 4(1)(4)) / 2(1). That give us (2 +/- sqroot -12) / 2. should be able to reduce that to 1 +/- (sqroot 3)i. So now we need to understand how to write the answer. Would it be 2x^2(x - (1 + [sqroot 3]i)(x + (1 + [sqroot 3]i)?? Some how this just does not appear to me to be the correct answer.
Thanks
Glenn and James
1 solutions
Answer 333035 by ankor@dixie-net.com(15746) on 2011-08-28 18:24:00 (Show Source):
You can put this solution on YOUR website!Factor the equation 2x^4 - 4x^3 + 8x^2
Let's see what I get here
2x^2(x^2 - 2x + 4)
first solution
2x^2 = 0
x = 0
:
Other solutions
x^2 - 2x + 4
using the complete the square method
x^2 - 2x + ____ = -4
complete the square
x^2 - 2x + 1 = -4 + 1
(x-1)^2 = -3
x - 1 = +/- 
x - 1 = +/- 
Two solutions
x = 1 +
x = 1 -
:
So we have x = 0, (1+ ) and (1- )
which is about what you had, except the 1st solution is x = 0 not 2x^2
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Numbers_Word_Problems/486564: There is a 3 digit number with each digit a different number. The sum of the digits is a perfect square. The sum of the first digit and the number made by the second and third digit is a perfect square.The product of the first digit and the number made by the second and third digit is a perfect square. What is the three digit number
1 solutions
Answer 333031 by ankor@dixie-net.com(15746) on 2011-08-28 17:58:33 (Show Source):
You can put this solution on YOUR website!No one seems to want to solve this problem and I haven't had much luck either but I wrote a basic problem to solve it
:
Run this Basic program
:
2 print " A program to find a 3 digit number where: Sum of the 3 digit is a perfect square"
4 print " The sum of the 1st digit & the number formed by the other two digits is a perfect square"
6 print " And the 1st digit times the number formed by the other digits is a perfect square also"
8 print: print
10 For a = 1 to 9
20 For b = 1 to 9
30 For c = 1 to 9
40 s = a+b+c
60 If SQR(s) = INT(SQR(s)) then 500
70 next c
80 next b
90 next a
95 end
100 print " ";a; b; c;" Is the number":end
500 u = a+(10*b)+c
510 if SQR(u) = INT(SQR(u)) then 600
520 goto 70
600 v = a*((10*b)+c)
610 if SQR(v) = INT(SQR(v)) then 100
629 goto 70
:
The results: 916 is the 3 digit number
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Travel_Word_Problems/486794: Working together, two men can do a job in 20 days. Working alone, however, it would take one man 9 days longer than it would take the other to complete the job. How long would it take each separately?
1 solutions
Answer 333030 by ankor@dixie-net.com(15746) on 2011-08-28 17:51:59 (Show Source):
You can put this solution on YOUR website!Working together, two men can do a job in 20 days.
Working alone, however, it would take one man 9 days longer than it would take the other to complete the job.
How long would it take each separately?
:
Let t = time required by the 1st man to do the job alone
then
(t+9) = time required by the 2nd man alone
:
Let the completed job = 1
:
A typical shared work equation
:
Each man will do a fraction of the job, the two fractions add up to 1
:
 +  = 1
:
multiply by t(t+9), results
20(t+9) + 20t = t(t+9)
20t + 180 + 20t = t^2 + 9t
:
Arrange as a quadratic equation
t^2 + 9t - 40t - 180 = 0
t^2 - 31t - 180 = 0
:
you can solve this using the quadratic equation, but it will factor to:
(t-36)(t+5) = 0
:
the positive solution
t = 36 days required by the 1st man
then
36 + 9 = 45 days required by the 2nd man
:
:
Check this
20/36 + 20/45
.56 + .44 = 1
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Square-cubic-other-roots/487160: (6x)4 when x=2
the four is to the fourth power. i do not want the answer but i need to now if i put six and x to the fourth power then multiply or if i multipy 6 and x then fourth power.
1 solutions
Answer 333028 by ankor@dixie-net.com(15746) on 2011-08-28 17:28:23 (Show Source):
You can put this solution on YOUR website!(6x)^4 when x=2
the four is to the fourth power.
:
Both 6 and x have to raised to the 4th power
:
You can replace x with 2
(6*2)^4 = 12^4
:
or you can write it
6^4 * x^4 = 1296x^4
:
Replace x with 2
1296*2^4 = 1296*16
:
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Finance/486469: I ihave two problems and need the detailed answers asap
1.Jogging: Two athletes jog 10 miles. One of the athletes jogs 2 miles per hour faster and finishes 10 minutes ahead of the other athlete. Find the average speed of each athlete.
2.Strength of a Beam: The strength of a beam varies jointly as its width w and the square of its thickness t. If a beam 8 inches wide and 5 inches thick supports 650 pounds, how much can a similar beam 6 inches wide and 6 inches thick support?
Please if I can get these asap Thank you so much
1 solutions
Answer 332612 by ankor@dixie-net.com(15746) on 2011-08-26 19:15:57 (Show Source):
You can put this solution on YOUR website!1.Jogging: Two athletes jog 10 miles. One of the athletes jogs 2 miles per hour faster and finishes 10 minutes ahead of the other athlete.
Find the average speed of each athlete.
Let s = jogging speed of the athlete
then
(s+2) = jogging speed of the faster athlete
:
Change 10 min to  hr
:
Write a time equation
:
slower time - faster time = 10 min
 -  =
multiply by 6s(s+2), resulting in
6(s+2)*10 - 6s(10) = s(s+2)
:
10(6s+12) - 60s = s^2 + 2s
:
60s + 120 - 60s = s^2 + 2s
Arrange to form a quadratic equation
s^2 + 2s - 120 = 0
Factors to
(s+12)(s-10) =
positive solution
s = 10 mph is the speed of the slower
then
10+2 = 12 mph is the speed of the faster
:
:
2.Strength of a Beam: The strength of a beam varies jointly as its width w and the square of its thickness t.
S = w*t^2*k,where k = the variation constant
:
If a beam 8 inches wide and 5 inches thick supports 650 pounds,
Find k
8*5^2*k = 650
200k = 650
k = 
k = 3.25
:
how much can a similar beam 6 inches wide and 6 inches thick support?
s = 6 *6^2*3.25
s = 702 lb can be support by a 6 by 6" beam
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Geometry_Word_Problems/486417: The length of a side of an equilateral triangle is the same as the length of a rectangle and the width of the rectangle is 2 inches less than its length. if the primeter of the triangle is 4 inches less than the primeter of the rectangle, what are the dimensions of the rectangle?
1 solutions
Answer 332564 by ankor@dixie-net.com(15746) on 2011-08-26 16:45:41 (Show Source):
You can put this solution on YOUR website!The length of a side of an equilateral triangle is the same as the length of a rectangle and the width of the rectangle is 2 inches less than its length.
if the perimeter of the triangle is 4 inches less than the perimeter of the rectangle, what are the dimensions of the rectangle?
:
Let x = the length of the side of the triangle and the length of the rectangle
then
(x-2) = the width of the rectangle
:
"the perimeter of the triangle is 4 inches less than the perimeter of the rectangle,"
3x = 2x + 2(x-2) - 4
3x = 2x + 2x - 4 - 4
3x = 4x - 8
3x - 4x = -8
-x = -8
therefore
x = 8 inches is the length of the rectangle (and the side of the triangle)
then
8 - 2 = 6 in is the width of rectangle
:
8 by 6 is the dimensions of the rectangle
:
:
See if that checks out:
Triangle 3(8) = 24 in
Rect: 2(8)+2(6) = 28 in
-----------------------
difference: 4 inches
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Word_Problems_With_Coins/486401: Mary has $5.00 in nickels, dimes, and quarters. If she has twice as many dimes as quarters and sixty-seven more nickels than dimes, how many coins of each type does she have?
quarters
dimes
nickels
1 solutions
Answer 332559 by ankor@dixie-net.com(15746) on 2011-08-26 16:35:03 (Show Source):
You can put this solution on YOUR website!Mary has $5.00 in nickels, dimes, and quarters.
If she has twice as many dimes as quarters and sixty-seven more nickels than dimes, how many coins of each type does she have?
:
Let: n = no. of nickels; d = no.of dimes; q = no of quarters
:
Write an equation for each statement:
:
"Mary has $5.00 in nickels, dimes, and quarters."
.05n + .10d + .25q = 5.00
:
"she has twice as many dimes as quarters"
d = 2q
divide both sides by 2
q = .5d
:
" sixty-seven more nickels than dimes,"
n = (d+67)
:
.05n + .10d + .25q = 5.00
Replace q with .5d, replace n with (d+67)
.05(d+67) + .10d + .25(.5) = 5.00
:
.05d + 3.35 + .10d + .125d = 5.00
:
.05d + .10d + .125d = 5.00 - 3.35
:
.275d = 1.65
d = 
d = 6 dimes
:
I'll let you find the nickels and quarters, check your solutions in the 1st equation.
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Polynomials-and-rational-expressions/486405: I don't know how to solve this problem.
A. For what value of y is the expression 12÷(y-2) undefined?________
B. Briefly explain why the expression is undefined for the value you noted in A.
thank you
1 solutions
Answer 332556 by ankor@dixie-net.com(15746) on 2011-08-26 16:12:43 (Show Source):
You can put this solution on YOUR website!A. For what value of y is the expression 12÷(y-2) undefined?________
B. Briefly explain why the expression is undefined for the value you noted in A.
:
Write it
An expression is undefined when the denominator = 0
therefore to find the value of y for this to occur
y - 2 = 0
y = +2
:
Expression is undefined when y = 2
:
Make sense?
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Travel_Word_Problems/486420: ?- Elizabeth is walking from her home to meet her friend Andrew and back again. She walks 2 km uphill, 6 km down hill, and 3 km on level ground. She takes the same route both ways. It takes her 6 hours for a round trip. How far did she walk?
Work- I tried to examine what the problem gave me. She walks 2 km uphill and 6 km down hill, but there was no clarification in the problem that she even walked on a hill. So, the fact that she walks 3 km on level ground is almost as obsolete because there's no guarantee that she walked on a level surface either. I did the work assuming that she would walk an entirely flat surface which is obviously 3x6=18km. If I assume she goes up and down each for an hour and the rest is flat it's 4+12+6=22km. If I find the average speed she walks (3x2x6/3) then I get that she walked 12 km. I feel like I could figure this problem better if I just knew what information from the original problem I am missing.
1 solutions
Answer 332554 by ankor@dixie-net.com(15746) on 2011-08-26 16:07:45 (Show Source):
You can put this solution on YOUR website!Elizabeth is walking from her home to meet her friend Andrew and back again.
She walks 2 km uphill, 6 km down hill, and 3 km on level ground.
She takes the same route both ways.
It takes her 6 hours for a round trip. How far did she walk?
:
They are just asking for the distance which is given as
one way; 2 + 6 + 3 = 11km, both ways would be 22 km
:
Up or down and time are irrelevant
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