Question

(b) determine the probability that a randomly selected fatal crash in 2020 occurred in daylight
the probability is 0.445
(round to three decimal places as needed )
(c) determine the probability that a randomly selected fatal crash in 2020 occurred in normal weather and in
daylight
the probability is 0.400
(round to three decimal places as needed )
(d) determine the probability that a randomly selected fatal crash in 2020 occurred in normal weather or in daylight
the probability is 0.931
(round to three decimal places as needed )
(e) would it be unusual for a fatal crash in 2020 to occur while it is dark outside (without light) and raining? why
might this result be considered misleading?
the probability that a randomly selected fatal crash in 2020 occurs when it is dark outside (without light) and raining
is
this value is 0.05, so it be unusual. this might be misleading because
people are driving when it is dark and raining

Explanation:

Step1: Calculate total number of fatal crashes

Sum up all values in the contingency table:

$$
LATEXBLOCK0
$$

Step2: Calculate number of fatal crashes when it is dark and raining

The value corresponding to "Dark" (under light condition) and "Rain" (under weather) is \(806\)

Step3: Calculate the probability

The probability \(P=\frac{\text{Number of dark - and - raining crashes}}{\text{Total number of crashes}}=\frac{806}{26617}\approx0.030\)

Since \(0.030<0.05\), it is unusual. This might be misleading because fewer people are driving when it is dark and raining.

Answer:

The probability that a randomly selected fatal crash in 2020 occurs when it is dark outside (without light) and raining is \(0.030\). This value is less than \(0.05\), so it would be unusual. This might be misleading because fewer people are driving when it is dark and raining.