James asked 60 pupils which drink they liked best from cola, milk and water.

32 boys were included in the survey.

12 of the boys said cola was their favourite.

4 boys liked water best and 9 girls liked water best.

21 pupils altogether said that milk was their preferred drink.

How many pupils altogether said that cola was their favourite drink?

26

Step-by-step explanation:

There are 60 pupils in the survey

32 are boys, so we assume 28 are girls

12 of the boys said cola was their favourite

4 boys liked water best.

That is a total of 16 boys who prefer either cola or water out of 32 total boys

There are 16 boys leftover who must have milk as there favourite

9 girls liked water best

21 pupils altogether said milk was there favourite. We know there are 16 boys who said milk was there favourite, meaning 5 of these pupils must be girls.

That means 9 girls have water as their favourite and 5 have milk as their favourite, a total of 14

We know there are 28 girls total. That means 14 of them must have listed cola as their favourite drink.

There are 14 girls and 12 boys who said cola was their favourite, a total of 26 pupils