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Finance/302052: I need help with this impossible problem
Jake has 6 coins.
Ellie has 12 coins.
There is a total of 5 quarters.
Jake has more than $1
Jake's coins are worth three times as much as Ellie's coins.
How much money does Jake have?
How much money does Ellie have?
My niece's teacher apparently wants us to show our work (my niece is in the 2nd grade and she somehow has this problem for a test. she's failing most of her tests and I want to find out why.) There is supposed to be a non-algebraic way to solve this problem since she is only in the 2nd grade. I hope you can reply soon. 1 solutions
Answer 216594 by josmiceli(9817) on 2010-05-08 17:08:27 (Show Source):
You can put this solution on YOUR website!2nd grade? I was taking remedial sandbox and advanced crayons.
This is a problem where she has to come to some logical
conclusions and put them together to get what they're
looking for
They don't say anything about it, but any number of pennies, nickels,
and dimes may be used
I focused on "Jake has more than $1"
(case #1) Jake could have 3 quarters and 3 dimes, giving him $1.05
(case #2) or, he could have 4 quarters, and it doesn't matter what the other 2 coins are
(case #3) 0r, he could have 5 quarters, and it doesn't matter what the other coin is
Now I look at "Jake's coins are worth 3 times Ellie's coins"
So, Jakes coins must be evenly divisible by 3
for case #1: 1.05/3 = .35
So, if Ellie has 12 coins, and I know 2 of them are quarters, she's already got
$.50, so case #1 doesn't work
for case #2: Jake could have:
$1.20 (4 quarters and 2 dimes)
$1.10 (4 quarters and 2 nickels)
$1.15 (4 quarters , a nickel and a dime)
$1.11 (4 quarters, a dime and a penny)
$1.06 (4 quarters, a nickel, and a penny)
$1.02 (4 quarters and 2 pennies)
The right one has to be evenly divisible by 3
$1.20/3 = .40
$1.11/3 = .37
$1.02/3 = .34
Now Ellie has 1 quarter, so her 11 remaining coins must add up to
.40 - .25 = .15
or
.37 - .25 = .12
or
.34 - .25 = .09
There's no way to get the last 2 with 11 coins, but
.15 = 10 pennies and a nickel
So, she ends up with 1 quarter, 10 pennies, and 1 nickel
when Jake has 4 quarters and 2 dimes
Now I just have to deal with case #3
Jake has either:
5 quarters and a dime = $1.35
5 quarters and a nickel = $1.30
5 quarters and a penny = $1.26
$1.35/3 = .45
$1.26/3 = .42
Nellie has 12 coins to make $.45
That would be 5 pennies, 6 nickels, and 1 dime
I can't seem to make $.42 with 12 coin, but no quarters
So, what I finally come up with is:
--------------------------------
When Jake has 4 quarters and 2 dimes,
Nellie has 1 quarter 1 nickel, 10 pennies
---------------------------------
When Jake has 5 quarters and 1 dime,
Nellie has 1 dime, 6 nickels, and 5 pennies
---------------------------------
Whew! What grade is she in?
This was hard for me. I'm still not sure I've
got all the answers and I've got 2 years of college
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Probability-and-statistics/302030: The Everton College store paid $1755 for an order of 49 calculators. The store paid $8 for each scientific calculator. The others, all graphing calculators, cost the store $55 each. How many of each type of calculator was ordered? 1 solutions
Answer 216581 by josmiceli(9817) on 2010-05-08 15:48:11 (Show Source):
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Linear-equations/302040: Here's another accuplacer practice question that I have no clue about: "write the slope intercept form of the equation (-2,0)and (7,4). The answer that lights up correct is Y=4/9x + 8/9. Can someone tell me why this is correct, and in general , how to write slope intercept forms? Thanks lots. 1 solutions
Answer 216578 by josmiceli(9817) on 2010-05-08 15:36:30 (Show Source):
You can put this solution on YOUR website!The formula to use when given 2 points is:

where the given points are:
(x1,y1) and (x2,y2)
It doesn't matter which is which, but I can call
(x1,y1) = (-2,0)
and
(x2,y2) = (7,4)
Putting these into the formula:

Multiply both sides by
 answer
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absolute-value/302032: Solve and write using interval notation: -3 < -5x + 7 <= 8
1 solutions
Answer 216575 by josmiceli(9817) on 2010-05-08 15:20:48 (Show Source):
You can put this solution on YOUR website!
This says 2 things:
(1) 
and
(2) 
Subtract  from both sides of (1)
(1) 
(1) 
Divide both sides by  and reverse < sign
(1) 
or,
(1) 
Now subtract  from both sides of (2)

Divide both sides by  and reverse sign

Or, what is the same thing:

Putting (1) and (2) together:
 answer
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Linear_Equations_And_Systems_Word_Problems/301785: approximately one half of all glass bottles distributed will be recycled each year. A beverage company distributes 310,000 bottles. the number in use after t
years is given by the function. N(t)=310,000(1/2)^t.
How many years will 5000 bottles still be in use?
I've tried several different ways to work this function and get a different answer every time!!!!!! Do Ineed to replace N for the 5000 to solve?
Thanks,
Desperately Trying 1 solutions
Answer 216438 by josmiceli(9817) on 2010-05-07 21:26:54 (Show Source):
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Travel_Word_Problems/301797: A helicopter goes 720 miles with the wind in the same time it can go 630 miles against
the wind. The speed of the wind is 6 miles per hour. Find the speed of the helicopter
with no wind. 1 solutions
Answer 216434 by josmiceli(9817) on 2010-05-07 21:15:22 (Show Source):
You can put this solution on YOUR website!Let  = speed of helicopter with no wind
 = speed of wind
given:
with the wind:

against the wind:

---------------
This is 2 equations with 2 unknowns
solve for  and
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Expressions-with-variables/301808: You have 6 trucks and 5 cars. Each truck pays twice as much as each car to use the toll. At the end of the day $12.75 was collected. Write the algebraic equation and solve the problem. 1 solutions
Answer 216430 by josmiceli(9817) on 2010-05-07 21:08:56 (Show Source):
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Miscellaneous_Word_Problems/301827: A 60% acid solution is to be mixed with a 80% acid solution to produce 20 liters of a 65% acid solution. How many liters of each solution is needed? I tried setting up a table but that didn't work. Can you please explain how you derive at your answer. Thanks and have a wonderful weekend. 1 solutions
Answer 216424 by josmiceli(9817) on 2010-05-07 20:58:41 (Show Source):
You can put this solution on YOUR website!Let  = liters of 60% solution needed
Let  = liters of 80% solution needed
given:
 = acid in 60% solution
 = acid in 80% solution
-----------------------
(1)  liters

(2) 
Multiply both sides of (1) by  and
subtract from (2)
(2) 
(1)

15 liters of 60% solution and 5 liters of 80% solution are needed
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Volume/301653: On her early morning walk, Jinhee noticed that when she walked under a streetlight, her shadow would get longer the farther she was away from the light. She decided to use her shadow to find out how tall the light was. When she was 21 feet from the base of the light, her shadow was 7 feet long. She is 5 feet 6 inches 1 solutions
Answer 216281 by josmiceli(9817) on 2010-05-07 09:28:17 (Show Source):
You can put this solution on YOUR website!There are 2 similar right triangles:
One is formed by her and her shadow
The other is formed by the streetlight
and (distance to her + her shadow)
I can write a ratio of the sides
of these similar triangles:
Let  = the height of the streetlight

multiply both sides by

The streetlight is 22 ft high
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Mixture_Word_Problems/301657: A chemist has some 8% hydrogen peroxide solution and some 3% hydrogen peroxide solution, how many milliliters of each should be used to make 500-milliliter solution that is 4%? 1 solutions
Answer 216277 by josmiceli(9817) on 2010-05-07 09:20:11 (Show Source):
You can put this solution on YOUR website!Let  = ml of 8% solution needed
Let  = ml of 3% solution needed
given:
hydrogen peroxide in 8% solution:
 ml
hydrogen peroxide in 3% solution:
 ml
-----------------

(1) 
and
(2) 
Multiply both sides of (2) by 
and subtract (2) from (1)
(1) 
(2)

and, since

100 ml of 8% solution and 400 ml of 3% solution are needed
check:

OK
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Linear-equations/301416: How would I graph c=30t+20? and also Media services charge $20 for a phone and $30/month for the economy plan, the equation c=30t+20 describes the total cost, c, of operating a media services phone for t months.what is total cost for 3 months of service? and also if a customer has $90 how many months of services can they get? Thanks so much 1 solutions
Answer 216196 by josmiceli(9817) on 2010-05-06 20:27:51 (Show Source):
You can put this solution on YOUR website!Plot  on the vertical axis, and  on
the horizontal axis
You plot it by plugging values of  into the equation
and finding  , like

Here's the plot:
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percentage/301358: A 60% acid solution is to be mixed with a
80% acid solution to produce 20 Liters of a
65% acid solution. How many liters of each
solution is needed? 1 solutions
Answer 216058 by josmiceli(9817) on 2010-05-06 13:25:23 (Show Source):
You can put this solution on YOUR website!Let  = liters of 60% solution needed
Let  = liters of 80% solution needed
given:
(1)  liters

(2) 
Multiply both sides of (1) by  and subtract (1) from (2)

and, since

15 liters of 60% solution and 5 liters of 80% solution are needed
check:
In words:
(liters of acid you end up with) / (final total liters of solution) = 65%

OK
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Money_Word_Problems/300978: I need help with this word math problem.
In a collection of nickels, dimes, and quarters, there are twice as many dimes as nickels, and fewer quarters than dimes. If the total value of the coins is $4.50, how many of each type of coin are there? 1 solutions
Answer 215858 by josmiceli(9817) on 2010-05-05 17:51:50 (Show Source):
You can put this solution on YOUR website!Let  = number of nickels
Let  = number of dimes
Let  = number of quarters
given:
 (in cents)

---------
By substitution:

I know that  , since quarters must add up to less than $4.50
If  then, suppose  ,  could be 
That's $2.75 plus $1.00 = $3.75. If there are twice as many dimes as
nickels,  , totaling $.25
$3.75 + $.25 = $4.00
My next guess is  ,  , 
You can go on from here, since you get the idea
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Radicals/300965: Please help me solve (2 radical 2)squared. I came up with the answer 4, as did the calculator but the book says the answer is 8. Can you show me how to solve this with the steps please? Thanks in advance! 1 solutions
Answer 215849 by josmiceli(9817) on 2010-05-05 17:31:44 (Show Source):
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Graphs/299969: Use the quadratic formula to determine the x-intercepts (if any) of the following function. Then evaluate the function for several values of x, and use the resulting points to graph the function. Show your work.
f(x) = 3x^2 1 solutions
Answer 215382 by josmiceli(9817) on 2010-05-03 16:52:22 (Show Source):
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Linear-equations/299962: What is the slope intercept form of a line that passes through point (0,2) and is parallel to the graph of y=-3x-6? 1 solutions
Answer 215375 by josmiceli(9817) on 2010-05-03 16:41:51 (Show Source):
You can put this solution on YOUR website!The equation  is in the form
 where  is the slope, so

Any line parallel to this line will also have 
I can write this equation as

To find  , I just plug in the (x,y) = (0,2)

So, the equation is
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Travel_Word_Problems/299982:
A motorboat takes 4 hours to travel 320 mi going upstream. The return trip takes hours 2 going downstream. What is the rate of the boat in still water and what is the rate of the current? 1 solutions
Answer 215370 by josmiceli(9817) on 2010-05-03 16:35:27 (Show Source):
You can put this solution on YOUR website!Let  = rate of boat in still water
Let  = rate of the current
Write 2 equations, one for upstream and one for downstream
given:
 hrs
 hrs
 mi
-----------
upstream:

(1) 
downstream:

(2) 
-----------------
(1) 
(2) 
Add the equations
 mi/hr
And, since
(1)
 mi/hr
The rate of the boat in still water is120 mi/hr
The rate of the current is 40 mi/hr
check:
(1)

and
(2)

OK
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