Need help with a math problem

Question

8 2/5 - 4 5/8 = can someone answer this math problem trying to help my grandson

Answer 1

8 2/5 - 4 5/8 = 42/5 - 37/8 = 336/40 - 185/40 =151/40

4 5/8 = 37/8 = 151/40

336/40 - 185/40 = 151/40 = 3 31/40 = 3.775

8.4 - 4.625 = 3.775

8 2/5 = 8.40

4 5/8 = 4.625.

8.4 - 4.625 = 3.775