Question

If n(aubuc)=100,n(a)=4x,n(b)=6x,n(c)=5x,n(a intersection b)=20,n(b intersection c)=15,n(a intersection c)=25,n(a intersection b intersection c)=10 .Then find x?

Answer 1

Answer:

n(aubuc)=n(a)+n(b)+n(c)-n(a intersection b)-n(b intersection c)-n(a intersection c)-n(a intersection b intersection c)

100=4x+6x+5x-20-15-25+10

100=15x-50

150=15x

X=10