Sean had an equal number of blueberry puffs, chocolate puffs and cream puffs. After he ate 22 blueberry puffs, some chocolate puffs and cream puffs, there were 47 puffs left. The number of chocolate puffs he ate was twice the number of cream puffs he ate. The number of chocolate puffs left was 12 more than the number of blueberry puffs left. How many blueberry puffs were there at first?

	Blueberry puffs	Chocolate puffs	Cream puffs	Total puffs
Before	1 p + 22	1 p + 2 u + 12	1 p + 2 u + 12
Change	- 22	- 2 u	- 1 u
After	1 p	1 p + 12	1 p + 12 + 1 u	47

Number of chocolate puffs and blueberry puffs was equal at first.

1 p + 2 u + 12 = 1 p + 22
2 u = 22 - 12
2 u = 10

1 u = 10 ÷ 2 = 5

Total number of puffs in the end
= 1 p + 1 p + 12 + 1 p + 12 + 5
= 1 p + 1 p + 1 p + 12 + 12 + 5
= 3 p + 29

3 p + 29 = 47
3 p = 47 - 29
3 p = 18

1 p = 18 ÷ 3 = 6

Number of blueberry puffs at first
= 1 p + 22
= 6 + 22
= 28

Answer(s): 28