Write two ratios that are equivalent to 1: 1

2:2
5:5

You do the same to one side as you would the other side. for example multiplying them both by 5 or 2

Hope this helps! :)

2:2 and 3:3 because 2:2 / 2:2 = 1:1 and 3:3 / 3:3 = 1:1

The answer for this question is 80