230 people went to a museum.
35 were children. Some adults joined halfway and the ratio of the number of children to the number of adults became 6 : 7. How many adults joined the museum halfway?
| |
Children |
Adults |
Total |
| Before |
3x2 =
6 u |
2x2 =
4 u |
5x2 =
10 u |
| Change |
|
+ ? |
|
| After |
6 u |
7 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 6 is 6.
Total number of people at first = 10 u
10 u = 230
1 u = 230 ÷ 10 = 23
Number of adults who joined halfway
= 7 u - 4 u
= 3 u
= 3 x 23
= 69
Answer(s): 69
