SOLUTION: Mary has $3.00 in nickels, dimes, and quarters. If she has twice as many dimes as quarters and five more nickels than dimes, how many coins of each type does she have?

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Question 171369This question is from textbook Precalculus
: Mary has $3.00 in nickels, dimes, and quarters. If she has twice as many dimes as quarters and five more nickels than dimes, how many coins of each type does she have? This question is from textbook Precalculus

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
.05N+.10D+.25Q=3.00
D=2Q
N=D+5 OR N=(2Q)+5
.05(2Q+5)+.10*2Q+.25Q=3.00
.10Q+.25+.20Q+.25Q=3.00
.55Q=3.00-.25
.55Q=2.75
Q=2.75/.55
Q=5 NUMBER OF QUARTERS.
D=2*5=10 NUMBER OF DIMES.
N=10+5=15 NUMBER OF NICKLES.
PROOF:
.05*15+.10*10+.25*5=3.00
.75+1+1.25=3.00
3.00=3.00