Answer:
There are 110 children total in the sports club
Step-by-step explanation:
To get this answer, its actually easier than it seems. You might need a calculator however.
First you start with the 11 children who play both badminton and squash, then, you divide that by 0.25 (25%) to get 44.
Next you take 44 and divide it by 0.4 (40%) to get 110.
And there you go! If you want to make sure you got it right simply start with 110 and multiply it by 0.4 then multiply the number/decimal you get by 0.25. You should get 11 to confirm your answer :)