# Suppose that the probabilities of a customer purchasing 0, 1, or 2 books at a book store are 0.2, 0.4, and 0.4, respectively. what is the expected number of books a customer will purchase? the standard deviation of the customer’s book purchases is

Posted On 05/29/2020

The correct answer was given: awdadaddda

Porobability distribution of xx p(x)0 0.21 0.42 0.4total .1.0i] expectationmean=σxpvariance=x²p-(∑xp)²thus: mean=(0*0.2)+(1*0.4)+(2*0.4)=0+0.4+0.8=1.2ii] variancevariance=[(0²*0.2)+(1²*0.4)+(2²*0.4)]-(1.2)²=[0+0.4+1.6]-1.44=0.56hence: standard deviation=sqrt(0.56)=0.74833

The correct answer was given: Brain

The answer would be A. 1 1/5

48/40 = 1 8/40

1 8/40 Simplify to 1 1/5

Hope this helps!

The correct answer was given: Brain

I believe it is 60-10=x because it says she purchased it with 60$ but recieved 10$ in change causing the amount we dont know to be a variable such as “x”