12 of the pupils in a school were boys and the rest were girls.
23 of the boys and
14 of the girls took part in a school event. 253 pupils took part. How many more girls were needed to take part in the school event so that it would be equal to the same number of boys who took part in the event?
Boys |
Girls |
1x12 = 12 u |
1x12 = 12 u |
Took part |
Did not take part |
Took part |
Did not take part |
2x4 |
1x4 |
1x3 |
3x3 |
8 u |
4 u |
3 u |
9 u |
Since
12 of the pupils in a school were boys and the rest were girls, the total number of boys and girls is the same.
The total number of boys is repeated and the total number of girls is repeated.
Make the total number of boys and the total number of girls the same since they are equal. LCM of 3 and 4 is 12.
Number of pupils who took part
= 8 u + 3 u
= 11 u
11 u = 253
1 u = 253 ÷ 11 = 23
Number of more girls that were needed to take part in the school event so that it would be equal to the same number of boys who took part in the event
= 8 u - 3 u
= 5 u
= 5 x 23
= 115
Answer(s): 115