Find two positive numbers whose ratio is 5:2 and whose product is 40

The two positive numbers are 10 and 4.

I factored 40.

1 x 40 = 40

2 x 20 = 40

4 x 10 = 40 * 4 and 10 divided by 2 is 2 and 5.

5 x 8 = 40

To check if my answer is correct, i did a cross multiplication: if the cross products are equal, then, one ratio is proportional to the other ratio.

a:b = c:d where ad = bc

5:2 = 10:4

5*4 = 2*10

20 = 20 They are proportional.