Answer:
The probability is 0.81
Step-by-step explanation:
The probability we want to find here is that;
the mail was delivered before 2 pm the first day and also delivered before 2 pm the next day
what we have to do here is to
multiply together, the probability in the two cases (for both days)
So we have this as:
0.9 * 0.9 = 0.81
