360 people went to a bird park.
34 were adults. Some children left halfway and the ratio of the number of adults to the number of children became 9 : 1. How many children left the bird park halfway?
| |
Adults |
Children |
Total |
| Before |
3x3 =
9 u |
1x3 =
3 u |
4x3 =
12 u |
| Change |
|
- ? |
|
| After |
9 u |
1 u |
|
Fraction of the people that were children at first
= 1 -
34 =
14 Number of adults remains unchanged. Make the number of adults the same. LCM of 3 and 9 is 9.
Total number of people at first = 12 u
12 u = 360
1 u = 360 ÷ 12 = 30
Number of children who left halfway
= 3 u - 1 u
= 2 u
= 2 x 30
= 60
Answer(s): 60
