Ch.12, Q.4, need answer for x2 with a). 0.11 and 82.7155 are wrong answers A par
ID: 3227757 • Letter: C
Question
Ch.12, Q.4, need answer for x2 with a). 0.11 and 82.7155 are wrong answersA particular report from 2004 classified 717 fatal bicycle accidents according to the month in which the accident occurred, resulting in the accompanying table. Month Number of Month Accidents January February March 42 April 60 May June July 97 84 August September ober 66 ovember 44 ecember 40 (a) Use the given data to test the null hypothesis Ho: T1 1/12, T2 1/12, 1T12 1/12, where T1 is the proportion of fatal bicycle accidents that occur in January, 112 is the proportion for February, and so on. Use a significance level of 0.01. (Use 2 decimal places.)
Explanation / Answer
(a) I will only do the part (a) only because only this portion has wrong answer. In part (b) you have calculated right answer.
Expected number of accidents in a month = average of accidents per month which can be calculated by taking average of all the values and divided by 12 = 717/12 = 59.75
Here below is the expected and observed table
so X2 critical = 82.72
(Just use two decimal places and put 82.72 in answer. It is the correct answer.
P - value = 0.00< 0.001 and conclusion is to reject the null hypothesis.
We have applied the same formula, please check answer again by putting value 82.72. there is no other method to solve it.
Month Accidents observed(Oi) Accidents Expected (Ei) (Oi -Ei)^2 (Oi -Ei)^2/Ei 1 36 59.75 564.06 9.44 2 31 59.75 826.56 13.83 3 42 59.75 315.06 5.27 4 60 59.75 0.06 0.00 5 78 59.75 333.06 5.57 6 75 59.75 232.56 3.89 7 97 59.75 1387.56 23.22 8 84 59.75 588.06 9.84 9 64 59.75 18.06 0.30 10 66 59.75 39.06 0.65 11 44 59.75 248.06 4.15 12 40 59.75 390.06 6.53 Sum 717 82.72