Question

please explain the answer

Answer 1

E={10,11,12,....40}

A={10,15,20,25,30,35,40}

B={12,18,24,30,36}

1)AUB={10,12,15,18,20,24,25,30,35,36,40}

A∩B={30}

2)n(AUB)=n(A)+n(B)-n(A∩B)

       11=7+5-1

11=12-1

11=11

LHS=RHS