Question 233816
Q+N=70 OR Q=70-N
.25Q+.05N=7.50
.25(70-N)+.05N=7.50
17.5-.25N+.05N=7.50
-.20N=7.50-17.50
-.20N=-10
N=-10/-.20
N=50 NICKLES IN THE JAR.
Q+50=70
Q=70-50
Q=20 QUARTERS IN THE JAR.
PROOF:
.25*20+.05*50=7.50
5.00+2.50=7.50
7.50=7.50