The number of cheese cakes on display at a cafe was
56 of the number of shortbreads on display. After 16 cheese cakes were bought and the staff added another 42 shortbreads, the number of shortbreads was thrice the number of cheese cakes. The last group of customers bought 6 shortbreads each, finishing all the shortbreads on display. How many customers were there in the last group?
| |
Cheese cakes |
Shortbreads |
| Before |
5 u |
6 u |
| Change |
- 16 |
+ 42 |
| After |
5 u - 16 |
6 u + 42 |
Comparing cheese cakes
and shortbreads
in the end |
1 |
3 |
The number of shortbreads was thrice the number of cheese cakes in the end.
Number of shortbreads in the end
= 3(5 u - 16)
= 15 u - 48
15 u - 48 = 6 u + 42 15 u - 6 u = 48 + 429 u = 90
1 u = 90 ÷ 9 = 10Number of shortbreads in the end= 6 u + 42= 6 x 10 + 42= 102Number of customers in the last group= 102 ÷ 6= 17 Answer(s): 17 
