Ivan had an equal number of strawberry cupcakes, butter cupcakes and vanila cupcakes. After he ate 32 strawberry cupcakes, some butter cupcakes and vanila cupcakes, there were 69 cupcakes left. The number of butter cupcakes he ate was four times the number of vanila cupcakes he ate. The number of butter cupcakes left was 16 more than the number of strawberry cupcakes left. How many strawberry cupcakes were there at first?

	Strawberry cupcakes	Butter cupcakes	Vanila cupcakes	Total cupcakes
Before	1 p + 32	1 p + 4 u + 16	1 p + 4 u + 16
Change	- 32	- 4 u	- 1 u
After	1 p	1 p + 16	1 p + 16 + 1 u	69

Number of butter cupcakes and strawberry cupcakes was equal at first.

1 p + 4 u + 16 = 1 p + 32
4 u = 32 - 16
4 u = 16

1 u = 16 ÷ 4 = 4

Total number of cupcakes in the end
= 1 p + 1 p + 16 + 1 p + 16 + 4
= 1 p + 1 p + 1 p + 16 + 16 + 4
= 3 p + 36

3 p + 36 = 69
3 p = 69 - 36
3 p = 33

1 p = 33 ÷ 3 = 11

Number of strawberry cupcakes at first
= 1 p + 32
= 11 + 32
= 43

Answer(s): 43