Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Please show steps. Thanks for your help 1. Ben drives to school for his class on

ID: 3072335 • Letter: P

Question

Please show steps. Thanks for your help

1. Ben drives to school for his class on Monday, Wednesday, and Friday. He prefers to park in parking lot A because the walk to class is shorter. If it is sunny the probability that he finds a spot is 0.7 but if it is raining more people drive, so the probability that he finds a spot is only 0.4. Whether he finds a spot in Lot A is independent from one day to another.

a. On a sunny day, what is the probability that Ben does not find a spot in Lot A?

b. In a week that is sunny on Monday and Friday and raining on Wednesday, what is the probability that Ben does not find a spot in Lot A on any of the 3 days?

c. In a week that is sunny on Monday and Friday and raining on Wednesday, what is the probability that Ben finds a spot in Lot A on at least one of the three days?

Explanation / Answer

________________________________________________

a)as we can see from contigency table,

P(no spot | sunny day ) = 0.3

____________________________________________

b)

P(no spot on monday being sunny ) =0.3

P(no spot on friday being sunny ) =0.3

P(no spot on wednesday being rainy ) =0.6

P(Ben does not find a spot in Lot A on any of the 3 days) = 0.3*0.3*0.6 =0.054

________________________________________________________________________

c)

P(Ben finds a spot in Lot A on at least one of the three days)= 1 - P(Ben does not find a spot in Lot A on any of the 3 days)

= 1 - 0.054

=0.946

spot no spot sunny 0.7 0.3 rainy 0.4 0.6