The following contingency table provides a joint frequency distribution for a group of retired people by career and age at retirement.
Find the probability that the person was a secretary or retired before the age of 61.
A)0.465
B)0.286
C)0.090
D)0.555
E)0.414

Question

The following contingency table provides a joint frequency distribution for a group of retired people by career and age at retirement. 
Find the probability that the person was a secretary or retired before the age of 61.
A)0.465 
B)0.286 
C)0.090 
D)0.555 
E)0.414

Quizplus · Accepted Answer

To find the probability that the person was a secretary or retired before the age of 61, we need to add up the frequency counts for those two categories and divide by the total frequency count.

The frequency count for retired before age 61 is 46 + 31 + 57 = 134. 
The frequency count for secretary is 26 + 15 = 41. 
The total frequency count is 134 + 49 + 38 + 26 + 15 + 12 = 274.

Therefore, the probability is (41 + 134)/274 = 0.465.

So, the best choice is A.

The Following Contingency Table Provides a Joint Frequency Distribution for a Group