Homework SourseJohn is a speed demon The probability that he will get a spe
| John is a speed demon. The probability that he will get a speeding ticket while driving to and from work is 30 percent. Answer the next three questions based on a work week (n = 5). | |||||||||
| 18 | What is the probability that John will get 2 tickets during the week (Monday-Friday)? | ||||||||
| a | 0.3087 | ||||||||
| b | 0.3364 | ||||||||
| c | 0.3441 | ||||||||
| d | 0.3717 | ||||||||
| 19 | What is the probability that John will get at least one ticket during the work week? | ||||||||
| a | 0.8985 | ||||||||
| b | 0.8319 | ||||||||
| c | 0.2496 | ||||||||
| d | 0.1681 | ||||||||
| 20 | If each ticket costs John $180 what is the average cost of speeding violation in the 5-day period? | ||||||||
| a | $260 | ||||||||
| b | $270 | ||||||||
| c | $280 | ||||||||
| d | $290 | ||||||||
| John is a speed demon. The probability that he will get a speeding ticket while driving to and from work is 30 percent. Answer the next three questions based on a work week (n = 5). | |||||||||
| 18 | What is the probability that John will get 2 tickets during the week (Monday-Friday)? | ||||||||
| a | 0.3087 | ||||||||
| b | 0.3364 | ||||||||
| c | 0.3441 | ||||||||
| d | 0.3717 | ||||||||
| 19 | What is the probability that John will get at least one ticket during the work week? | ||||||||
| a | 0.8985 | ||||||||
| b | 0.8319 | ||||||||
| c | 0.2496 | ||||||||
| d | 0.1681 | ||||||||
| 20 | If each ticket costs John $180 what is the average cost of speeding violation in the 5-day period? | ||||||||
| a | $260 | ||||||||
| b | $270 | ||||||||
| c | $280 | ||||||||
| d | $290 | ||||||||
Solution
18.
Note that the probability of x successes out of n trials is
P(n, x) = nCx p^x (1 - p)^(n - x)
where
n = number of trials = 5
p = the probability of a success = 0.3
x = the number of successes = 2
Thus, the probability is
P ( 2 ) = 0.3087 [ANSWER, A]
**************
19.
Note that the probability of x successes out of n trials is
P(n, x) = nCx p^x (1 - p)^(n - x)
where
n = number of trials = 5
p = the probability of a success = 0.3
x = the number of successes = 0
Thus, the probability is
P ( 0 ) = 0.16807
Thus, P(at least one) = 1 - P(0) = 0.83193 [ANSWER, B]
***************
20.
As
E(x) = n p
Then
E(180x) = 180 n p = 180*5*0.3 = 270 [ANSWER, B]
