There was an equal number of lemons and dragonfruits. On Thursday, some lemons were added, such that the number of lemons increased by 80%. On Friday, the number of lemons further increased by 50% and the number of dragonfruits decreased by 20%. There were 19 more lemons than dragonfruits in the end. How many lemons and dragonfruits were there altogether at first?

	Lemons	Dragonfruits
Before	1 u	1 u
Change 1	+ 0.8 u	No change
After 1	1.8 u	1 u
Change 2	+ 0.9 u	- 0.2 u
After 2	2.7 u	0.8 u

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

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

Number of dragonfruits decreased on Friday
= 20% x 1 u
= ²⁰₁₀₀ x 1 u
= 0.2 u

Number of more lemons than dragonfruits in the end
= 2.7 u - 0.8 u
= 1.9 u

1.9 u = 19

1 u = 19 ÷ 1.9 = 10

Total number of lemons and dragonfruits at first
= 1 u + 1 u
= 2 u
= 2 x 10
= 20

Answer(s): 20