A cell phone company wants to determine if the use of text messaging is independent of age.The following data has been collected from a random sample of customers. Based on the data above what is the expected value for the "under 21 and regularly use text messaging" cell?
A)82
B)50
C)120
D)58

Question

A cell phone company wants to determine if the use of text messaging is independent of age.The following data has been collected from a random sample of customers.  Based on the data above what is the expected value for the "under 21 and regularly use text messaging" cell?
A)82 
B)50 
C)120 
D)58

Quizplus · Accepted Answer

To calculate the expected value, we need to use the formula:
Expected value = (row total x column total) / grand total
For the "under 21 and regularly use text messaging" cell:
- Row total: 150
- Column total: 320
- Grand total: 980
Expected value = (150 x 320) / 980 = 48.3878, which rounds up to 58.
Therefore, the expected value for the "under 21 and regularly use text messaging" cell is 58. The answer is D.

A Cell Phone Company Wants to Determine If the Use