There were some mangosteens, persimmons and chikoos. The number of mangosteens was four times the number of persimmons. The total number of mangosteens and persimmons was half of the number of chikoos. There were 180 fruits altogether. All the chikoos were sold at 4 for $15. How much money was collected from the sale of the chikoos?
Number of persimmons = 1 u
Number of mangosteens = 4 u

Total number of persimmons and mangosteens
= 1 u + 4 u
= 5 u

Number of chikoos
= 2 x 5 u
= 10 u

Total number of fruits
= 1 u + 4 u + 10 u
= 15 u

15 u = 180

1 u = 180 ÷ 15 = 12

Number of chikoos sold
= 10 u
= 10 x 12
= 120

Number of sets of 4 chikoos
= 120 ÷ 4
= 30

Amount collected from the sale of chikoos
= 30 x 15
= $450

Answer(s): $450