Answer:
The probability that at least 1 is more careful about personal information when using a public Wi-Fi hotspot is 0.987.
Correct option is (A).
Step-by-step explanation:
Let <em>X</em> = number of Internet users who are more careful about personal information when using a public Wi-Fi hotspot.
The probability of the random variable <em>X</em> is, <em>p</em> = 0.66.
A random sample of <em>n</em> = 4 internet users are selected.
The random variable <em>X</em> follows a Binomial distribution with parameters <em>n</em> = 4 and <em>p</em> = 0.66.
The probability mass function of <em>X</em> is:
Compute the probability that at least 1 is more careful about personal information when using a public Wi-Fi hotspot as follows:
P (X ≥ 1) = 1 - P (X < 1)
= 1 - P (X = 0)
Thus, the probability that at least 1 is more careful about personal information when using a public Wi-Fi hotspot is 0.987.
If the survey subjects volunteered to respond to the survey, then the sampling method used is Volunteering sampling. This type of sampling involves bias caused by the subjects known as voluntary response bias.
The bias occurs because the people could be responding uninterested in the survey or they could be emotionally driven to answer the survey.
This bias can affect the probability of the random variable, causing a huge probability of success.
Many people uses public wifi so the proportion of people more careful must be high.
So the correct option is (A).