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2.4.13 Model with probability distributions

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Question 5

Automated security software monitors login attempts for potential breaches. For a specific category of low-risk attempts, the probability that the software fails to flag the attempt is 0.06. A security audit reviews these attempts in independent blocks of 50.

a.

Determine the probability that a single block of 50 contains no more than 2 unflagged attempts.

[3]
b.

The auditor evaluates 12 such independent blocks. Find the probability that fewer than 3 of these blocks contain at most 2 unflagged attempts.

[4]
c.

Using a suitable approximation, estimate the probability that the total number of unflagged attempts across the 12 blocks is more than 45.

[4]

2.4.13 Model with probability distributions Questions

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