SOLUTION: Velma has $6.25 in nickels, dimes and quarters. She has twice as many quarters as nickels and five fewer dimes than quarters. How many of each type of coin does she have

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Question 1200381: Velma has $6.25 in nickels, dimes and quarters. She has twice as many quarters as nickels and five fewer dimes than quarters. How many of each type of coin does she have
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39623) About Me  (Show Source):
You can put this solution on YOUR website!
n, d, q
nickels, dimes, quarters
5n%2B10d%2B25q=625
n%2B2d%2B5q=125

system%28q%2Fn=2%2Cand%2Cq-d=5%29
system%28n%2Fq=1%2F2%2Cq-5=d%29
OR
system%28n=q%2F2%2Cd=q-5%29---------substitute into the money equation.

highlight_green%28%28q%2F2%29%2B2%28q-5%29%2B5q=125%29
q%2B4%28q-5%29%2B10q=250
q%2B4q-20%2B10q=250
15q-20=250
15q=270
highlight%28q=18%29-----------and you can find the other two coins.

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!
Velma has $6.25 in nickels, dimes and quarters. She has twice as many quarters as nickels and five fewer dimes than quarters. How many of each type of coin does she have 

Let number of nickels be N
Then number of quarters = 2N
And, number of dimes = 2N - 5
We then get: .05N + .25(2N) + .1(2N - 5) = 6.25
                   .05N + .5N + .2N - .5 = 6.25
                                    .75N = 6.75
                Number of nickels, or 

You should now be able to find the number of quarters (2N), and dimes (2N - 5)!!