Answer:
Step-by-step explanation:
Consider the ratio in the format
girls → 12
boys → 15
You can not have parts of a person so we need the least number of pupils that we can have in this ratio.
girls
boys
→ 12 ÷ 3
15 ÷ 3 = 4/5
As 5 is a prime number we can not go any smaller.
If we have 4 girls and 5 boys it gives a total of
4 + 5 = 9
in the smallest possible group.
It is known that 3 groups of 9 gives 27 pupils. 27 pupils is all the class.
