Verified answer

5*3 = 15

15+10 = 25

25 * 2 = 50

1.5 * 3 = 4.5

4.5 + 10 = 14.5

14.5 * 2 = 29

12*3= 36

36 + 10 = 46

46 *2 = 92

x * 3 = 3x

3x + 10

(3x + 10) * 2 = 6x + 20