Using the least common factor, it is found that there are 672 pupils.
The factorization is:
24 - 28 - 32|2
12 - 14 - 16|2
6 - 7 - 8|2
3 - 7 - 4|2
3 - 7 - 2|2
3 - 7 - 1|3
1 - 7 - 1|7
1 - 1 - 1
[tex]\text{lcm}(24,28,32) = 2^5 \times 3 \times 7 = 32 \times 21 = 672[/tex]
There are 672 pupils.
A similar problem is given at https://brainly.com/question/21329937