Question

QUESTION 3 Given two events, A and B, such that P(A) = 0.4, P(B) 0.3, and P(A| B) 0.5, find P(A or B). QUESTION 4 Find the probability of 1 or fewer heads on six coin flips. QUESTION 5 Save All Answers to save all ansuers.

Answer 1

3)

P(A)=0.4

P(B)=0.3

P(A|B)=0.5

P(A or B)=P(A) + P(B) - P(A|B) * P(B) = 0.4+0.3 - 0.5*0.3 = 0.55

4)

it is a binomial probability distribution, because there is fixed number of trials,  
only two outcomes are there, success and failure  
trails are independent of each other  
and probability is given by  

P(X=x) = C(n,x)*px*(1-p)(n-x)

where  
Sample size , n =    6
Probability of an event of interest,P(Head) ,   p =   0.5

P ( X = 0) = C (6,0) * 0.5^0 * ( 1 - 0.5)^6=      0.0156
P ( X = 1) = C (6,1) * 0.5^1 * ( 1 - 0.5)^5=      0.0938

P(1 or fewer heads) = P(X≤1) = P(X=0) + P(X=1)=0.0156+0.0938=0.1094(answer)