There were 3 times as many boys as girls at a party. After 4 girls left, the number of boys was 9 times the number of the remaining girls. How many people attended the party?
| |
Boys |
Girls |
Total |
| Before |
3x3 =
9 u |
1x3 =
3 u |
12 u |
| Change |
|
- 4 |
|
| After |
9 u |
1 u |
|
The number of boys at first and in the end remains unchanged. Make the number of boys the same. LCM of 3 and 9 is 9.
Number of girls who left
= 3 u - 1 u
= 2 u
2 u = 4
1 u = 4 ÷ 2 = 2
Number of people who attended the party
= 9 u + 3 u
= 12 u
= 12 x 2
= 24
Answer(s): 24
