The number of cream cakes on display at a cafe was
23 of the number of cookies on display. After 22 cream cakes were bought and the staff added another 42 cookies, the number of cookies was thrice the number of cream cakes. The last group of customers bought 6 cookies each, finishing all the cookies on display. How many customers were there in the last group?
|
Cream cakes |
Cookies |
Before |
2 u |
3 u |
Change |
- 22 |
+ 42 |
After |
2 u - 22 |
3 u + 42 |
Comparing cream cakes and cookies in the end |
1 |
3 |
The number of cookies was thrice the number of cream cakes in the end.
Number of cookies in the end
= 3(2 u - 22)
= 6 u - 66
6 u - 66 = 3 u + 42 6 u - 3 u = 66 + 423 u = 108
1 u = 108 ÷ 3 = 36Number of cookies in the end= 3 u + 42= 3 x 36 + 42= 150Number of customers in the last group= 150 ÷ 6= 25 Answer(s): 25