Deaths from Car Crashes Randomly selected deaths from car crashes were obtained,

Question

Deaths from Car Crashes Randomly selected deaths from car crashes were obtained, and the results are included below (based on data from the Insurance Institute for Highway Safety). Use a 0.05 significance level to test the claim that car crash fatalities occur with equal frequency on the different days of the week. How might the results be explained? Why does there appear to be an exceptionally large number of car crash fatalities on Saturday?
Day (Number of fatalities) Sun(132) Mon(98) Tues(95) Wed(98) Thurs(105) Fri(133) Sat(158).

a) Test Statistic:
b) Critical X2 :
c) P-Value:
d) Conclusion:

Explanation / Answer

Chi-square statistics=(132-117)^2/117+(98-117)^2/117+(95-117)^2/117+(98-117)^2/117+(105-117)^2/117+(133-117)^2/117+(158-117)^2/117=30

Critical value=chi-square(0.05,6)=12.6

Since Chi-square statistics> Critical value, we reject the conjecture that car crash fatalities occur with equal frequency on the different days of the week. We see that there are many crash on Friday, Saturday and Sunday because many people drive on these days.

The P-Value is 3.9E-05 or 0.000039

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