In: Statistics and Probability
In a survey from all the 1,000 families in a small city, 355 of the families have health insurance coverage from their work place, 256 of the families purchase the health insurance all by themselves, 260 of the families do not have health insurance, and the rest of the 129 families did not reply. If a family is selected at random from this city in the study what is the probability that this family either does not have health insurance or did not reply to the survey?
Solution: We are given:
The total families in a small city,
The number of families who have health insurance coverage from their work
The number of families who have purchased health insurance by themselves
The number of families who do not have health insurance
The number of families who did not reply
Let A be the number of familes who do not have health insurance and B be the number of families who did not reply. Therefore, we have:
Now we have to find, if a family is selected at random from this city in the study what is the probability that this family either does not have health insurance or did not reply to the survey.
In other words, we have to find
Since event A and B are mutually exclusive, therefore we have:
Therefore,the probability that the family selected at random either does not have health insurance or did not reply to the survey is 0.389