Asked Mar 7, 2020

Rework problem 15 from section 4.3 of your text, involving the expected number of heads when flipping one of two coins. One coin is fair and one is weighted so that Pr[H]=1/7. You randomly select one of the two coins, and flip it 2 times, noting the result of each flip.

What is the expected number of heads?


Expert Answer

Step 1

Let, X= the number of heads

X follows a binomial distribution with parameters n and p.

For the fair coin n= 2 and p=1/2 

So the expected number of heads on the fair coin is:

Probability homework question answer, step 1, image 1


For the weighted coin n=2 and p=1/7

So, the expected number of heads on the weighted coin is:

Probability homework question answer, step 1, image 2



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