Question 106920
N+D=50 OR N=50-D
.05(50-D)+.10D=3.50
2.5-.05D+.10D=3.50
.05D=3.50-2.50
.05D=1.00
D=1.00/.05
D=20 NUMBER OF DIMES.
50-20=30 NUMBER OF NICKLES.
PROOF
.05*30+.10*20=3.50
1.50+2.00=3.50
3.50=3.50