PSLE
A fruit seller had an equal number of starfruits, passion fruits and mangosteens at first. After 78 mangosteens, some starfruits and passion fruits were sold, there were 142 fruits left. There were 2 times as many starfruits as passion fruits left. The number of mangosteens left was 18 less than the number of starfruits left. How many passion fruits were sold?

	Starfruits	Passion Fruits	Mangosteens	Total
Before	1	1	1
Change	- ?	- ?	- 78
After	2 u	1 u	2 u - 18	142

Total number of fruits in the end
= 2 u + 1 u + 2 u - 18
= 5 u - 18

5 u - 18 = 142
5 u = 142 + 18
5 u = 160

1 u = 160 ÷ 5 = 32

Number of mangosteens at first
= 2 u - 18 + 78 
= 2 x 32 + 60 
= 124 

The number of mangosteens and passion fruits at first is the same.

Number of passion fruits sold
= 124 - 32
= 92

Answer(s): 92