Question

With all the talk about distracted drivers, a community outreach group in Bradford, VT reached out to the Vermont State Police and asked for and received the following data about cell phone use and speeding violations. Use this data to find the following probabilities.

	Speeding violation in the last year	No speeding violation in the last year
Cell phone user	40	430
Not a cell phone user	25	150

1. Find P(Person is a car phone user)

2. Find P(person had no violation in the last year)

3. Find P(Person had no violation in the last year AND was a car phone user)

4. Find P(Person is a car phone user OR person had no violation in the last year).

5. Find P(Person is a car phone user GIVEN person had a violation in the last year)

6. Find P(Person had no violation last year GIVEN person was not a car phone user)

(Please show all of your work, Thank you!)

Answer 1

	speeding violation	no speeding violation	total
cell phone user	40	430	470
not a cell phone user	25	150	175
total	65	580	645

1) P(Person is a car phone user) =470/645

2) P(person had no violation in the last year) =580/645

3) P(Person had no violation in the last year AND was a car phone user) =430/645

4) P(Person is a car phone user OR person had no violation in the last year)=(470+580-430)/645=620/645

5) P(Person is a car phone user GIVEN person had a violation in the last year) =40/65

6) P(Person had no violation last year GIVEN person was not a car phone user) =150/175