There were some persimmons, passion fruits and mangosteens. The number of persimmons was five times the number of passion fruits. The total number of persimmons and passion fruits was one-third of the number of mangosteens. There were 168 fruits altogether. All the mangosteens were sold at 6 for $13. How much money was collected from the sale of the mangosteens?
Number of passion fruits = 1 u
Number of persimmons = 5 u

Total number of passion fruits and persimmons
= 1 u + 5 u
= 6 u

Number of mangosteens
= 3 x 6 u
= 18 u

Total number of fruits
= 1 u + 5 u + 18 u
= 24 u

24 u = 168

1 u = 168 ÷ 24 = 7

Number of mangosteens sold
= 18 u
= 18 x 7
= 126

Number of sets of 6 mangosteens
= 126 ÷ 6
= 21

Amount collected from the sale of mangosteens
= 21 x 13
= $273

Answer(s): $273