Question

5/r=4/16

Answer 1

5/r = 1/4

r = 20

Answer 2

We start again by simplifying the fraction on the right:

4/16 = 1/4

so 5/r = 1/4

Multiply the right side by 5/5 and 1/4 becomes 5/20

So 5/r = 5/20

and r = 20. :)