Question

1. A man has 5 grandchildren, 4 girls and 1 boy. He thinks this is unusual. If the probability that any child born

will be a girl is 1/2, what is the probability that a person who has 5 grandchildren will have exactly 4
granddaughters? Is this case unusual? Explain.
2 To be on the safe side three detectors were installed in a facton moon

Answer 1

6.25%

Explanation:

To know the final probability that this has happened, we must multiply the probability of each event, they tell us that the probability that it is a girl is 1/2 and this happened 4 times, therefore:

(1/2) ^ 4 = 0.0625

that is, the probability that 4 girls are born is 6.25%

an unusual probability is considered when it is less than 5%, therefore, although it approaches this figure, it is not unusual