Answer to Question #39189 in Algebra for John Walker

Question

Software filters rely heavily on “blacklists” (lists of known “phishing” URLs) to detect fraudulent e-mails. But such filters typically catch only 15 percent of phishing URLs. Jason receives 10 phishing e-mails.

(a)
What is the expected number that would be caught by such a filter? (Round your answer to the next whole number.)

Expected number

(b)
What is the chance that such a filter would detect none of them? (Round your answer to 5 decimal places.)

Probability