Question 242339
N+D=10 OR N=10-D
.05N+.10D=.80
.05(10-D)+.10D=.80
.5-.05D+.10D=.80
.05D=.80-.50
.05D=.30
D=.30/.05
D=6 DIMES.
10-6=4 NICKELS.
PROOF:
.05*4+.10*6=.80
.20+.60=.80
.80=.80