There were thrice as many boys as girls at a party. After 18 girls left the party, there were five times as many boys as girls who remained behind. How many boys were there at the party?
|
Boys |
Girls |
Before |
3x5 = 15 u |
1x5 = 5 u |
Change |
|
- 18 |
After |
5x3 = 15 u |
1x3 = 3 u |
The number of boys remained unchanged. Make the number of boys the same. LCM of 3 and 5 is 15.
Decrease in the number of girls
= 5 u - 3 u
= 2 u
2 u = 18
1 u = 18 ÷ 2 = 9
Number of boys
= 15 u
= 15 x 9
= 135
Answer(s): 135