The ratio of the number of tarts in Container J to the number of tarts in Container K was 7 : 5. 40% of the tarts in Container J and 0.7 of those in Container K were strawberry. After transferring the tarts between the 2 containers, the number of mango tarts in both containers are the same. Likewise, the number of strawberry tarts in both containers are the same. If a total of 238 tarts were moved, how many more tarts were there in Container J than Container K at first?

Container J		Container K
7 u		5 u
Strawberry	Mango	Strawberry	Mango
2.8 u	4.2 u	3.5 u	1.5 u
+ 0.35 u	- 1.35 u	- 0.35 u	+ 1.35 u
3.15 u	2.85 u	3.15 u	2.85 u

Number of strawberry tarts in Container J
= 40% x 7 u
= ⁴⁰₁₀₀ x 7 u
= 2.8 u

Number of mango tarts in Container J
= 7 u - 2.8 u
= 4.2 u

Number of strawberry tarts in Container K
= 0.7 x 5 u
= 3.5 u

Number of mango tarts in Container K
= 5 u - 3.5 u
= 1.5 u

Number of strawberry tarts in each container in the end
= (2.8 u + 3.5 u) ÷ 2
= 6.3 u ÷ 2
= 3.15 u

Number of mango tarts in each container in the end
= (4.2 u + 1.5 u) ÷ 2
= 5.7 u ÷ 2
= 2.85 u

Number of tarts moved
= 0.35 u + 1.35 u
= 1.7 u

1.7 u = 238

1 u = 238 ÷ 1.7 = 140

Number of more tarts in Container J than Container K at first
= 7 u - 5 u
= 2 u
= 2 x 140
= 280

Answer(s): 280