probability of A and B

Question

Given the sample space with P(A only)=0,7and P(B only)=0,2 ;

Determine :

2.1.1. P(A and B) 

2.1.2. P(A or B), if A and B are mutually exlusive

Answer 1

   P(A and B) = P(A) * P(B) = 0.7 * 0.2 = 0.14

 

  P(A or B) = P(A) + P(B) - P( A and B) = 0.7 + 0.2 - 0.14 = 0.9 - 0.14 = 0.76