480 people went to a park.
35 were adults. Some children left halfway and the ratio of the number of adults to the number of children became 12 : 5. How many children left the park halfway?
| |
Adults |
Children |
Total |
| Before |
3x4 =
12 u |
2x4 =
8 u |
5x4 =
20 u |
| Change |
|
- ? |
|
| After |
12 u |
5 u |
|
Fraction of the people that were children at first
= 1 -
35 =
25 Number of adults remains unchanged. Make the number of adults the same. LCM of 3 and 12 is 12.
Total number of people at first = 20 u
20 u = 480
1 u = 480 ÷ 20 = 24
Number of children who left halfway
= 8 u - 5 u
= 3 u
= 3 x 24
= 72
Answer(s): 72
