Fifteen minutes ago, 60% of the students in a hall were girls. 36 more students entered the hall. As a result, the number of girls increased by 20% and the number of boys increased by 70%. How many students are in the hall now?
| |
Girls |
Boys |
Total |
| Before |
5 u |
2 u |
7 u |
| Change |
+ 1 u |
+ 1.4 u |
+ 2.4 u |
| After |
6 u |
3.4 u |
9.4 u |
60% =
60100 =
35Number of more girls who entered the hall
= 20% x 5 u
=
20100 x 5 u
= 1 u
Number of more boys who entered the hall
= 70% x 2 u
=
70100 x 2 u
= 1.4 u
Total number of more students who entered the hall
= 1 u + 1.4 u
= 2.4 u
2.4 u = 36
1 u = 36 ÷ 2.4 = 15
Number of students in the hall now
= 6 u + 3.4 u
= 9.4 u
= 9.4 x 15
= 141
Answer(s): 141
