330 people went to a park.
35 were children. Some adults joined halfway and the ratio of the number of children to the number of adults became 9 : 10. How many adults joined the park halfway?
|
Children |
Adults |
Total |
Before |
3x3 = 9 u |
2x3 = 6 u |
5x3 = 15 u |
Change |
|
+ ? |
|
After |
9 u |
10 u |
|
Fraction of the people that were adults at first
= 1 -
35 =
25 Number of children remains unchanged. Make the number of children the same. LCM of 3 and 9 is 9.
Total number of people at first = 15 u
15 u = 330
1 u = 330 ÷ 15 = 22
Number of adults who joined halfway
= 10 u - 6 u
= 4 u
= 4 x 22
= 88
Answer(s): 88