Question

In a survey of consumers aged 12 and​ older, respondents were asked how many cell phones were in use by the household.​ (No two respondents were from the same​ household.) Among the​ respondents, 212 answered​ "none," 288 said​ "one," 371 said​ "two," 148 said​ "three," and 82 responded with four or more. A survey respondent is selected at random. Find the probability that​ his/her household has four or more cell phones in use. Is it unlikely for a household to have four or more cell phones in​ use? Consider an event to be unlikely if its probability is less than or equal to 0.05.

Answer 1

P(a randomly selected household has four or more cell phones in use) = Number of households with 4 or more cell phones in use / Total number of households surveyed

= 82/(212+288+371+148+82)

= 82/1101

= 0.0745

It is not unlikely for a household to have four or more cell phones in​ use because the probability of the event is greater than 0.05