In a survey of a TriDelt chapter with 50 members, 20 were taking mathematics, 32 were taking English, and 6 were taking both. How many were not taking either of these subjects?

Answer 1

just recall the rule that

total = one + other - both.

So, counting just the ones taking something, you have

20+32-6 = 46

So, the other 4 took nothing.