Suppose that Maria has 140 coins consisting of pennies, nickels, and dimes. The number of nickels she has is 12 less than twice the number of pennies; the number of dimes she has is 22 less than three times the number of pennies. How many coins of each kind does she have?

2 answers

p+n+d = 140
n = 2p-12
d = 3p-22

(p,n,d) = (29,46,65)
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