Tim had an equal number of cream cookies, vanila cookies and butter cookies. After he ate 64 cream cookies, some vanila cookies and butter cookies, there were 79 cookies left. The number of vanila cookies he ate was four times the number of butter cookies he ate. The number of vanila cookies left was 24 more than the number of cream cookies left. How many cream cookies were there at first?
| |
Cream cookies |
Vanila cookies |
Butter cookies |
Total cookies |
| Before |
1 p + 64 |
1 p + 4 u + 24 |
1 p + 4 u + 24 |
|
| Change |
- 64 |
- 4 u |
- 1 u |
|
| After |
1 p |
1 p + 24 |
1 p + 24 + 1 u |
79 |
Number of vanila cookies and cream cookies was equal at first.
1 p + 4 u + 24 = 1 p + 64
4 u = 64 - 24
4 u = 40
1 u = 40 ÷ 4 = 10
Total number of cookies in the end
= 1 p + 1 p + 24 + 1 p + 24 + 10
= 1 p + 1 p + 1 p + 24 + 24 + 10
= 3 p + 58
3 p + 58 = 79
3 p = 79 - 58
3 p = 21
1 p = 21 ÷ 3 = 7
Number of cream cookies at first
= 1 p + 64
= 7 + 64
= 71
Answer(s): 71
