There were thrice as many boys as girls at a parade. After 20 girls left the parade, there were five times as many boys as girls who remained behind. How many boys were there at the parade?
| |
Boys |
Girls |
| Before |
3x5 =
15 u |
1x5 =
5 u |
| Change |
|
- 20 |
| 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 = 20
1 u = 20 ÷ 2 = 10
Number of boys
= 15 u
= 15 x 10
= 150
Answer(s): 150
