Warren had an equal number of butter puffs, chocolate puffs and blueberry puffs. After he ate 27 butter puffs, some chocolate puffs and blueberry puffs, there were 36 puffs left. The number of chocolate puffs he ate was twice the number of blueberry puffs he ate. The number of chocolate puffs left was 11 more than the number of butter puffs left. How many butter puffs were there at first?

	Butter puffs	Chocolate puffs	Blueberry puffs	Total puffs
Before	1 p + 27	1 p + 2 u + 11	1 p + 2 u + 11
Change	- 27	- 2 u	- 1 u
After	1 p	1 p + 11	1 p + 11 + 1 u	36

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

1 p + 2 u + 11 = 1 p + 27
2 u = 27 - 11
2 u = 16

1 u = 16 ÷ 2 = 8

Total number of puffs in the end
= 1 p + 1 p + 11 + 1 p + 11 + 8
= 1 p + 1 p + 1 p + 11 + 11 + 8
= 3 p + 30

3 p + 30 = 36
3 p = 36 - 30
3 p = 6

1 p = 6 ÷ 3 = 2

Number of butter puffs at first
= 1 p + 27
= 2 + 27
= 29

Answer(s): 29