The average number of chikoos in Box Q, Box R and Box S is 24 and it is 8 more than the average number of mangoes in the 3 boxes. ¹₃ of the mangoes are in Box Q and the mangoes in Box Q is 80% of the number of mangoes in Box R. If each box has the same number of fruits, what percentage of the fruits in Box S are chikoos?
Average number of mangoes
= 24 - 8
= 16

Total number of mangoes
= 3 x 16
= 48

Total number of chikoos
= 3 x 24 
= 72

Total number of fruits
= 48 + 72
= 120

Number of fruits in each box
= 120 ÷ 3
= 40

Mangoes in Box Q	Mangoes in Box R	Mangoes in Box S	Total mangoes
1x4	2x4		3x4
4x1	5x1
4 u	5 u	3 u	12 u

80% = ⁸⁰₁₀₀ = ⁴₅

The number of mangoes in Box Q is repeated.  Make the number of mangoes in Box Q the same.  LCM of 1 and 4 is 4. 

Total number of mangoes
= 4 u + 5 u + 3 u
= 12 u

12 u = 48

1 u = 48 ÷ 12 = 4

Number of mangoes in Box S
= 3 u
= 3 x 4
= 12

Number of chikoos in Box S
= 40 - 12
= 28

Percentage of the fruits in Box S are chikoos
= ²⁸₄₀ x 100%
= 70%

Answer(s): 70%