Question

How many nickels and dimes are in $1.20 if there are six times more nickels than dimes

Answer 1

You are told that:

n=6d and 10d+5n=120 (using cents :P) now using n from the first equation in the second equation gives you:

10d+5(6d)=120

10d+30d=120

40d=120

d=3, and since n=6d

n=18

So there are 3 dimes and 18 nickels.