The number of durian cakes on display at a cafe was
34 of the number of puffs on display. After 25 durian cakes were bought and the staff added another 40 puffs, the number of puffs was thrice the number of durian cakes. The last group of customers bought 4 puffs each, finishing all the puffs on display. How many customers were there in the last group?
|
Durian cakes |
Puffs |
Before |
3 u |
4 u |
Change |
- 25 |
+ 40 |
After |
3 u - 25 |
4 u + 40 |
Comparing durian cakes and puffs in the end |
1 |
3 |
The number of puffs was thrice the number of durian cakes in the end.
Number of puffs in the end
= 3(3 u - 25)
= 9 u - 75
9 u - 75 = 4 u + 40 9 u - 4 u = 75 + 405 u = 115
1 u = 115 ÷ 5 = 23Number of puffs in the end= 4 u + 40= 4 x 23 + 40= 132Number of customers in the last group= 132 ÷ 4= 33 Answer(s): 33