50% of the pupils are girls. 50% of the girls and 60% of the boys wear watches. What percentage of the pupils do not wear watches?
| Girls |
Boys |
Total |
| 50% |
50% |
100% |
| Wear watches |
Do not wear |
Wear watches |
Do not wear |
|
| 25% |
25% |
30% |
20% |
100% |
Number of girls who wear watches
= 50% x 50%
=
50100 x 50%
= 25%
Number of boys who wear watches
= 60% x 50%
=
60100 x 50%
= 30%
Percentage of pupils who wear watches
= 25% + 30%
= 55%
Percentage of pupils who do not wear watches
= 100% - 55%
= 45%
Answer: 45%
