Example 4-33: Parking TicketsBluman 5th ed. © McGraw Hill

The probability that Sam parks in a no-parking zone and gets a parking ticket is 0.06, and the probability that Sam cannot find a legal parking space and has to park in the no-parking zone is 0.20. On Tuesday, Sam arrives at school and has to park in a no-parking zone. Find the probability that he will get a parking ticket.

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Bluman’s Example 4-33: Parking TicketsWRITE OUT DEFINITIONS! Let T = gets a ticket event,Let N = parks in a no-parking zone event.

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What the problem says What it means in algebra

Parking in a no-parking zone Call it event N

Getting a ticket Call it event T

P(no parking zone and ticket is 0.06) P(N and T) = 0.06

P(he has to park in a no-parking zone) is 0.20 P(N) = 0.20

If he parks in a no-parking zone, find probability he will get a ticket

P(T | N) = ?

Example 4-33: Parking TicketsBluman 5th ed. © McGraw Hill

Event N: he parks in a no-parking zoneEvent T: he gets a parking ticketThey ask “Probability he gets a ticket, given that he parks in a no-parking zone”, that is, P(T|N)Formula: Computation:

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