Question

If you want to divide 4 by 2/5 you can multiply 4 by 5, then divide it by 2 or multiply it by 1/2.

Answer 1

Step-by-step explanation:

to divide by a fraction is the same as to multiply by the upside-down fraction.

in your example

4 / 2/5 = 4 × 5/2 = 20/2 = 10

by the way, also a whole number is a fraction.

4 = 4/1

so, fully formal, the whole operation above looks like

(4/1) / (2/5) = (4/1) × (5/2) = (4×5) / (1×2) = 20/2 = 10/1 = 10