The average number of kiwis in Box Q, Box R and Box S is 18 and it is 4 more than the average number of lemons in the 3 boxes. ¹₇ of the lemons are in Box Q and the lemons in Box Q is 30% of the number of lemons in Box R. If each box has the same number of fruits, what percentage of the fruits in Box S are kiwis?
Average number of lemons
= 18 - 4
= 14

Total number of lemons
= 3 x 14
= 42

Total number of kiwis
= 3 x 18 
= 54

Total number of fruits
= 42 + 54
= 96

Number of fruits in each box
= 96 ÷ 3
= 32

Lemons in Box Q	Lemons in Box R	Lemons in Box S	Total lemons
1x3	6x3		7x3
3x1	10x1
3 u	10 u	8 u	21 u

30% = ³⁰₁₀₀ = ³₁₀

The number of lemons in Box Q is repeated.  Make the number of lemons in Box Q the same.  LCM of 1 and 3 is 3. 

Total number of lemons
= 3 u + 10 u + 8 u
= 21 u

21 u = 42

1 u = 42 ÷ 21 = 2

Number of lemons in Box S
= 8 u
= 8 x 2
= 16

Number of kiwis in Box S
= 32 - 16
= 16

Percentage of the fruits in Box S are kiwis
= ¹⁶₃₂ x 100%
= 50%

Answer(s): 50%