There were 350 pupils in a school. On the school anniversary,
34 of the boys and
23 of the girls came in black blazers. The rest came in blue blazers. The number of girls who wore blue blazers was twice of the boys who wore blue blazers. How many pupils were in black blazers that day?
| Boys |
Girls |
Total |
| Black blazers |
Blue blazers |
Black blazers |
Blue blazers |
|
| 3 |
1 |
2x2 |
1x2 |
|
| |
1 |
|
2 |
|
| 3 u |
1 u |
4 u |
2 u |
10 u |
The number of girls who came in blue blazers is repeated. Make the number of girls who came in blue blazers the same. LCM of 1 and 2 is 2.
Total number of pupils
= 3 u + 1 u + 4 u + 2 u
= 10 u
10 u = 350
1 u = 350 ÷ 10 = 35
Number of pupils in black blazers
= 3 u + 4 u
= 7 u
= 7 x 35
= 245
Answer(s): 245
