The probability that she gets audited no more than 2 times is 0.896482...
As, a pair of dice are rolling here, so the number of total possible outcome = (6×6) = 36
For Sum = 7 , the favorable outcomes are: (1,6) (2,5) (3,4) (4,3) (5,2) and (6,1)
For Sum = 11 , the favorable outcomes are: (5,6) and (6,5)
For Sum = 12 , the favorable outcome is: (6,6)
Probability = (Number of favorable outcomes)÷(Number of total outcomes)
So,
P( 7 or 11 or 12) =
Here the total number of trials = 5 and the probability of getting audited =
According the binomial distribution formula:
P(X) = (ⁿCₓ )(P)ˣ (1-P)ⁿ⁻ˣ
where P(X) is the probability of x successes out of n trials
Here, n= 5 and P = 1/4 and we need to find the probability of getting audited no more than 2 times. This means she can gets audited 0, 1 or 2 times.
So,
So, the probability that she gets audited no more than 2 times is 0.896482...