There were some persimmons, starfruits and apples. The number of persimmons was two times the number of starfruits. The total number of persimmons and starfruits was half of the number of apples. There were 180 fruits altogether. All the apples were sold at 8 for $7. How much money was collected from the sale of the apples?
Number of starfruits = 1 u
Number of persimmons = 2 u

Total number of starfruits and persimmons
= 1 u + 2 u
= 3 u

Number of apples
= 2 x 3 u
= 6 u

Total number of fruits
= 1 u + 2 u + 6 u
= 9 u

9 u = 180

1 u = 180 ÷ 9 = 20

Number of apples sold
= 6 u
= 6 x 20
= 120

Number of sets of 8 apples
= 120 ÷ 8
= 15

Amount collected from the sale of apples
= 15 x 7
= $105

Answer(s): $105