Answer to Question #188913 in Statistics and Probability for kel

Question

If the probability of finding working light bulbs in a factory in a warehouse that stores them is the same as our probabilities of finding working light bulbs in a box (as in our problem above), what is the (a.) expected number of light bulbs that will work given you pick out 50? (You can assume replacement/independence here because our warehouse holds thousands of light bulbs).

Answer 1

Consider that probability is $= 0.5 = p$

Then,

We have $n = 50$

a.) Hence, expectation $\lambda = n \times p= 0.5 \times 50 = 25$