Answer:
Dimes = 9 coins
Nickels = 12 coins
Step-by-step explanation:
N + D = 21 ---> N = 21 - D
.05N + .1D = 1.5
Substitute N = 21 - D into .05N + .1D = 1.5
.05(21 - D) + .1D = 1.5
1.05 - .05D + .1D = 1.5
.05D = .45
D = 9
N = 21 - 9
N = 12
Dimes = 9 coins
Nickels = 12 coins
