Which Day Is The Party?
Bob recently fell of his ladder whilst cleaning a first floor window. He had quite a nasty bang on the head, and he can't quite remember when his friend's birthday is. He can't think whether it was in August or July. He does remember it is in the last 3 days of the month it is in, though. He was invited to his friend's birthday party, which is on his birthday. What is the probability of him going to his friend's house on the right day? Put your answer as a decimal, please round to 2 decimal places.
The answer is 0.17.
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1 solution
Three days for each month makes it 6 possible birthdays. Considering them equally probable the answer is 6 1