Question

In a group of people 50 people, 31 like tea, 20 like coffe and 6 like both tea and coffee. Find how many like tea

Answer 1

I think 46 people like tea

Answer 2

In a group of 50 people, 31 like tea, 20 like coffee and 6 like both tea and coffee. Find how many like tea?

n(A) = n(A - B) + n(A ∩ B)

→ n(A - B) = n(A) - n(A ∩ B)

= (31 - 6) = 25.

So, 25 like tea.