Glen had an equal number of chocolate cookies, blueberry cookies and cream cookies. After he ate 36 chocolate cookies, some blueberry cookies and cream cookies, there were 52 cookies left. The number of blueberry cookies he ate was four times the number of cream cookies he ate. The number of blueberry cookies left was 16 more than the number of chocolate cookies left. How many chocolate cookies were there at first?

	Chocolate cookies	Blueberry cookies	Cream cookies	Total cookies
Before	1 p + 36	1 p + 4 u + 16	1 p + 4 u + 16
Change	- 36	- 4 u	- 1 u
After	1 p	1 p + 16	1 p + 16 + 1 u	52

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

1 p + 4 u + 16 = 1 p + 36
4 u = 36 - 16
4 u = 20

1 u = 20 ÷ 4 = 5

Total number of cookies in the end
= 1 p + 1 p + 16 + 1 p + 16 + 5
= 1 p + 1 p + 1 p + 16 + 16 + 5
= 3 p + 37

3 p + 37 = 52
3 p = 52 - 37
3 p = 15

1 p = 15 ÷ 3 = 5

Number of chocolate cookies at first
= 1 p + 36
= 5 + 36
= 41

Answer(s): 41