SOLUTION: mary has $3.75 in nickels,dimes,quarters. she has three more quarters than dimes. she has twice as many nickels as quarters. how many of each coin does she have?

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Question 291389: mary has $3.75 in nickels,dimes,quarters. she has three more quarters than dimes. she has twice as many nickels as quarters. how many of each coin does she have?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
mary has $3.75 in nickels,dimes,quarters. she has three more quarters than dimes. she has twice as many nickels as quarters. how many of each coin does she have?
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Equations:
Value Eq:::: 5n + 10d + 25q = 375 cents
Quantity:::: q = d + 3
Quantity:::: n = 2q
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Substitute for "d" dnd for "n" and solve for "q":
5(2q) + 10(q-3) + 25q = 375
10q + 10q - 30 + 25q = 375
45q = 405
q = 9 (# of quarters)
n = 2q = 18 (# of quarters)
d = q-3 = 6 (# of dimes)
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Cheers,
Stan H.