130 people went to a museum.
25 were adults. Some children left halfway and the ratio of the number of adults to the number of children became 4 : 3. How many children left the museum halfway?
|
Adults |
Children |
Total |
Before |
2x2 = 4 u |
3x2 = 6 u |
5x2 = 10 u |
Change |
|
- ? |
|
After |
4 u |
3 u |
|
Fraction of the people that were children at first
= 1 -
25 =
35 Number of adults remains unchanged. Make the number of adults the same. LCM of 2 and 4 is 4.
Total number of people at first = 10 u
10 u = 130
1 u = 130 ÷ 10 = 13
Number of children who left halfway
= 6 u - 3 u
= 3 u
= 3 x 13
= 39
Answer(s): 39