Answer:
Step-by-step explanation:
Let n represent nickels & d dimes
given: n + d = 25 #1 (number of coins)
given: .05n + .10d = 1.65 #2 (amount in dollars)
n = 25 - d #3 (rewrite of #1)
.05(25 -d) + .10d = 1.65 (substitute #3 in #2)
1.25 - .05d + .10d = 1.65 (multiply out the left side)
.05d = .40 (collection of like terms)
d = 8 (divided both sides by.05)
n + 8 = 25 (substitute answer for d in #1)
n = 17 (subtract both sides by 8)
There are 8 dimes and 17 nickels.
Check:
17(.05) + 8(.10) = 1.65 (answers in #2)
.85 + .80 = 1.65 (multiply out the left side)
1.65 = 1.65 ✔️ QED
