There are some pupils in the zoo.
310 of them are girls, of whom 10% of them do not wear watches.
17 of the boys do not wear watches. What is the percentage of the pupils in the zoo who do not wear watches?
| Girls |
Boys |
Total |
3x10 =
30 u |
7x10 =
70 u |
10x10 =
100 u |
| No watches |
Watches |
No watches |
Watches |
|
| 1x3 |
9x3 |
1x10 |
6x10 |
|
| 3 u |
27 u |
10 u |
60 u |
100 u |
10% =
10100=
110 The number of girls is the repeated identity. Make the number of girls the same. LCM of 3 and 10 is 30.
Number of pupils who do not wear watches
= 3 u + 10 u
= 13 u
Total number of pupils
= 3 u + 27 u + 10 u + 60 u
= 100 u
Percentage of the pupils in the zoo who do not wear watches
=
13100 x 100%
= 13%
Answer(s): 13%
