Question

A school knows that 38% of its incoming students own a smart phone and a tablet.what percent of students who own a smartphone also own a tablet if 84% of students own a smart phone

Answer 1

No. of students own a smart phone=B= 84%
No.of students own a tablet=A
No. of students own a smart phone and tablet= A∩B =38%

We use the conditional probability to do this problem;
Pr(A|B)=Pr(A∩B)/Pr(B)
=0.38/0.84
=0.45
=45%(no. of students own a smartphone also own a tablet)