Stephen has 90 fish. He sold 1/2 of them and gave 1/3 of them to Cody. What faction of the fish was left? How many fish did he give Cody?

Answer 1

1/2 = 3/6
1/3 = 2/6

6/6 - 5/6 = 1/6

1/3 * 90 = 30