Answer:
b. 42 people
Step-by-step explanation:
For each foreigner living in the U.S., there are only two possible outcomes. Either they are naturalized citizens, or they are not. The probability of a foreigner living in the U.S. not being a naturalized citizen is independent from other foreigners living in the U.S. So we use the binomial probability distribution to solve this problem.
Binomial probability distribution
Probability of exactly x sucesses on n repeated trials, with p probability.
The expected value of the binomial distribution is:
"approximately 60% of foreign-born people who live in the U.S. are not naturalized citizens"
This means that
70 foreign-born people who live in the U.S
This means that
How many people would you expect to get that are not naturalized citizens?
So the correct answer is:
b. 42 people