Question

In a group of students ,50%like tea,70%like coffee,10%dont like both and 120% like both .Find total number of students.

Answer 1

n(u)=50

n(t)=70

n(c)=10

n(tnc)=120

n(tuc)=x(let)

we know that

n(u)=n(t)+n(c)+n(tnc)+n(tuc)

50=70+10+120+x(let)

50=200+x

x=200–50

x=150

n(tuc)=150

it help you