483 people went to a concert hall.
57 were adults. Some children joined halfway and the ratio of the number of adults to the number of children became 15 : 8. How many children joined the concert hall halfway?
| |
Adults |
Children |
Total |
| Before |
5x3 =
15 u |
2x3 =
6 u |
7x3 =
21 u |
| Change |
|
+ ? |
|
| After |
15 u |
8 u |
|
Fraction of the people that were children at first
= 1 -
57 =
27 Number of adults remains unchanged. Make the number of adults the same. LCM of 5 and 15 is 15.
Total number of people at first = 21 u
21 u = 483
1 u = 483 ÷ 21 = 23
Number of children who joined halfway
= 8 u - 6 u
= 2 u
= 2 x 23
= 46
Answer(s): 46
