Question

The probability of getting a defective bottle from a manufacturer is 0.05. A sample of 10 bottles were selected. Calculate the probability of getting 2 defective bottles.

Answer 1

Solution

Let X represent the defective bottles

$P(X) =0.05$

$X\backsim B(10,0.05)$

$P(X=2)=$

$^{10}C_2(0.95)^{10-2}(0.05)^2$

$P(X=2)=45(0.66342).(0.05^2)$

$P(X=2)=0.0017$