There are some pupils in the school hall.
710 of them are boys, of whom 60% of them do not wear watches.
23 of the girls do not wear watches. What is the percentage of the pupils in the school hall who do not wear watches?
| Boys |
Girls |
Total |
7x5 =
35 u |
3x5 =
15 u |
10x5 =
50 u |
| No watches |
Watches |
No watches |
Watches |
|
| 3x7 |
2x7 |
2x5 |
1x5 |
|
| 21 u |
14 u |
10 u |
5 u |
50 u |
60% =
60100=
35 The number of boys is the repeated identity. Make the number of boys the same. LCM of 7 and 5 is 35.
Number of pupils who do not wear watches
= 21 u + 10 u
= 31 u
Total number of pupils
= 21 u + 14 u + 10 u + 5 u
= 50 u
Percentage of the pupils in the school hall who do not wear watches
=
3150 x 100%
= 62%
Answer(s): 62%
