609 people went to a safari park.
47 were adults. Some children joined halfway and the ratio of the number of adults to the number of children became 12 : 11. How many children joined the safari park halfway?
|
Adults |
Children |
Total |
Before |
4x3 = 12 u |
3x3 = 9 u |
7x3 = 21 u |
Change |
|
+ ? |
|
After |
12 u |
11 u |
|
Fraction of the people that were children at first
= 1 -
47 =
37 Number of adults remains unchanged. Make the number of adults the same. LCM of 4 and 12 is 12.
Total number of people at first = 21 u
21 u = 609
1 u = 609 ÷ 21 = 29
Number of children who joined halfway
= 11 u - 9 u
= 2 u
= 2 x 29
= 58
Answer(s): 58