Kara has 162 coins in her collection of nickels, dimes, and quarters, which has a total value of 22 dollars If Kara has twleve fewer nickels than quarters, how many dimes does she have?
q = quarters value = 25q
n = nickels = q-12 value = 5(q-12)
d = dimes= 162- q - (q-12) = 162-2q+12 = 174-2q value = 10(174-2q) Summed, these all equal 2200 (22 dollars in cents)
so
25q + 5(q-12) + 10 (174-2q) = 2200 solve for q then dimes = 174-2q