Salik's school organized a trip to Belgium. At first, the ratio of the number of girls to the number of boys who planned to participate in the trip was 7 : 5. On the day of registration, 6 boys decided to withdraw and 6 more girls decided to join in. In the end, the number of boys who participated became 25% of the total children for the trip. How many more girls than boys would visit Belgium in the end?

	Girls	Boys	Total
Before	7x1 = 7 u	5x1 = 5 u	12x1 = 12 u
Change	+ 2 u	- 2 u
After	3x3 = 9 u	1x3 = 3 u	4x3 = 12 u

25% = ²⁵₁₀₀ = ¹₄

Since 6 boys withdrew and another 6 girls joined, the total number of children  at first and in the end remains unchanged. Make the total number of children the same. LCM of 12 and 4 is 12.

Number of boys who decided to withdraw
= 5 u - 3 u
= 2 u

2 u = 6

1 u = 6 ÷ 2 = 3

Number of more girls than boys in the end
= 9 u - 3 u
= 6 u
= 6 x 3
= 18

Answer(s): 18