Question: If 24 out of every 60 individuals like football and out of those that like it, 50% play it, how many people would you expect play football out of a group of 250?
Solve this problem. 
Answer: 
If 50% of individuals that like football play it, and there are 24 out of 60 individuals that like it, then 24*50% = 12 out of 60 individuals play it
If 12 individuals play it out of 60 individuals then that means only 12/60 = 1/5 or 20% play it
If 20% of individuals play football out of a group of 250 people, one would expect 250*20% = 50 individuals to play it