There are some pupils in the bird park.
25 of them are girls, of whom 80% of them do not wear watches.
23 of the boys do not wear watches. What is the percentage of the pupils in the bird park who do not wear watches?
Girls |
Boys |
Total |
2x5 = 10 u |
3x5 = 15 u |
5x5 = 25 u |
No watches |
Watches |
No watches |
Watches |
|
4x2 |
1x2 |
2x5 |
1x5 |
|
8 u |
2 u |
10 u |
5 u |
25 u |
80% =
80100=
45 The number of girls is the repeated identity. Make the number of girls the same. LCM of 2 and 5 is 10.
Number of pupils who do not wear watches
= 8 u + 10 u
= 18 u
Total number of pupils
= 8 u + 2 u + 10 u + 5 u
= 25 u
Percentage of the pupils in the bird park who do not wear watches
=
1825 x 100%
= 72%
Answer(s): 72%