Math question Algebra need help

Question

Michael has a jar full of dimes and quarters. There are a total of 120 coins with a total value of $19.20. The system of equations below represents this situation.

How many MORE dimes than quarters are in Michael's jar?

A.12

B.15

C.24

D.48

Answer 1

Let we have x dimes, then (120 - x) is number of quarters. So, bank 10x + 25(120 - x) = 1920;

10x - 25x = 1920 - 3000; - 15x = - 1080; x = 72; 120 - 72 = 48;

72 - 48 = 24

Answer: dimes 24 more then quarters