Question 1013555
5N+10D+25Q = 500
N=3D
25Q=5(5N) >>> This tells me that Q=N

5(3D)+10D+25(3D)= 500

15D+10D+75D=500

100D=500

D=5

N=Q=15

15 nickels is $0.75
5 dimes is $0.50
15 quarters is $3.75 

total $5.

Check the other relationships work. Always check once you solve.