There was an equal number of chikoos and persimmons. On Thursday, some chikoos were added, such that the number of chikoos increased by 80%. On Friday, the number of chikoos further increased by 50% and the number of persimmons decreased by 10%. There were 36 more chikoos than persimmons in the end. How many chikoos and persimmons were there altogether at first?

	Chikoos	Persimmons
Before	1 u	1 u
Change 1	+ 0.8 u	No change
After 1	1.8 u	1 u
Change 2	+ 0.9 u	- 0.1 u
After 2	2.7 u	0.9 u

Number of chikoos added on Thursday
= 80% x 1 u
= ⁸⁰₁₀₀ x 1 u
= 0.8 u

Number of chikoos increased on Friday
= 50% x 1.8 u
= ⁵⁰₁₀₀ x 1.8 u
= 0.9 u

Number of persimmons decreased on Friday
= 10% x 1 u
= ¹⁰₁₀₀ x 1 u
= 0.1 u

Number of more chikoos than persimmons in the end
= 2.7 u - 0.9 u
= 1.8 u

1.8 u = 36

1 u = 36 ÷ 1.8 = 20

Total number of chikoos and persimmons at first
= 1 u + 1 u
= 2 u
= 2 x 20
= 40

Answer(s): 40