Bryan's school organized a trip to Thailand. At first, the ratio of the number of boys to the number of girls who planned to participate in the trip was 7 : 5. On the day of registration, 6 girls decided to withdraw and 6 more boys decided to join in. In the end, the number of girls who participated became 25% of the total children for the trip. How many children would visit Thailand in the end?
|
Boys |
Girls |
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 =
14Since 6 girls withdrew and another 6 boys 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 girls who decided to withdraw
= 5 u - 3 u
= 2 u
2 u = 6
1 u = 6 ÷ 2 = 3
Number of children that would visit Thailand in the end
= 9 u + 3 u
= 12 u
= 12 x 3
= 36
Answer(s): 36