Question

If a binomial experiment involves flipping a fair coin four times and counting the number of heads that result, the probability of at least three heads turning up in four flips is what?

A mobile provider believes that its new promotion will convince 20% of their competitors' customers to switch to their own service. If the company's forecasts are correct, what is the approximate probability that one out of four randomly selected competitors' customers will switch after exposure to the promotion?

Important characteristics of the Poisson distribution include which of the following? (I) The random variable is the number of occurrences of some event over some defined interval. (II) The probability of the event is proportional to the size of the chosen interval. (III) The intervals do not overlap. (IV) The occurrences are dependent on one another.

Answer 1

1. The probability of obtaining a head in toss of a fair coin = 0.5.

The probability of obtaining at least 3 heads in 4 tosses = = 0.3125 (Ans).

2. The probability that one out of four randomly selected competitors customers will switch to their own service = = 0.4096 (Ans).

3. Important characteristic of Poisson distribution is:

The random variable is the number of occurrences of some event over some defined interval. (Ans).