A store owner has 100 less chikoos than passion fruits. After he sold 80% of the chikoos and 10% of the passion fruits, he is left with 36 less chikoos than passion fruits. What fraction of the fruits left were chikoos?

	Chikoos		Passion fruits
Comparing chikoos and passion fruits at first			100 less
Before	5x2 = 10 u	+ 100	10x1 = 10 u
Change	- 4x2 = - 8 u	- 80	- 1x1 = - 1 u
After	1x2 = 2 u	+ 20	9x1 = 9 u
Comparing chikoos  and passion fruits in the end	36 less

80% = ⁸⁰₁₀₀ = ⁴₅ 
80% x 100 = ⁴₅ x 100 = 80
100 - 80 = 20

10% = ¹⁰₁₀₀ = ¹₁₀ 

The number of chikoos is 36 less than the number of passion fruits in the end. So, if another 36 chikoos are added, the number of chikoos and passion fruits in the end will be the same.

2 u + 20 + 36 = 9 u
2 u + 56 = 9 u
9 u - 2 u = 56
7 u = 56

1 u = 56 ÷ 7 = 8

Number of chikoos left
= 2 u + 20
= 2 x 8 + 20
= 16 + 20
= 36

Total number of fruits left
= 2 u + 20 + 9 u
= 11 u + 20
= 11 x 8 + 20
= 88 + 20
= 108

^{Chikoos left}_{Total fruits left} = ³⁶₁₀₈ = ¹₃

Answer(s): ¹₃