first you'll want to convert the mixed number to an improper fraction.
your result is (5/3), so now you can divide the two fractions more easily:
(7/8) ÷ (5/3)
to divide fractions, the rule to remember is "flip the second fraction and multiply them" and here you'll do that. flip (5/3) so that it's (3/5), then multiply them
(7/8) × (5/3)
multiplying straight across the top gives you 7 × 5, or 35.
multiplying straight on the bottom row gives you 8 × 3, or 24.
your resulting fraction is 35/24, which can't be further reduced