Question

Based on a Comcast survey there is a 0.8 probability that a randomly selected adult will watch prime-time TV live, instead of online, on VR , etc. Assume that seven adults are randomly selected. HINT: binomial distribution. Show all work, if you use the calculator state what input you used. Round to 4 decimal places.

a. Find the probability that exactly 1 of the selected adults watch prime-time TV live?

b. Find the probability that fewer than 3 selected adults watch prime-time TV live?

c. Find the probability that at least 1 selected adult watches prime-time TV live?

Answer 1

Let's consider X be the number of adults watch prime-time TV live.

Hence X is model by the binomial distribution with parameter n=7 and p=0.8

a) The probability that exactly 1 of the selected adults watch prime-time TV live is given by:

### By using r command:

> dbinom(1,7,0.8)
[1] 0.0003584

b) The probability that fewer than 3 selected adults watch prime-time TV live is given by:

### By using R command:

> pbinom(2,7,0.8)
[1] 0.004672

c) The probability that at least 1 selected adult watches prime-time TV live is given by

#### By using r command:

> 1-pbinom(0,7,0.8)
[1] 0.9999872