Handedness and Cell Phone Use The accompanying table is from a study conducted with the stated objective of addressing cell phone safety by understanding why we use a particular ear for cell phone use. (See “Hemispheric Dominance and Cell Phone Use,” by Seidman, Siegel, Shah, and Bowyer, JAMA Otolaryngology—Head & Neck Surgery, Vol. 139, No. 5.)

The goal was to determine whether the ear choice is associated with auditory or language brain hemispheric dominance. Assume that we want to test the claim that handedness and cell phone ear preference are independent of each other.

a. Use the data in the table to find the expected value for the cell that has an observed frequency of 3.

Round the result to three decimal places.

b. What does the expected value indicate about the requirements for the hypothesis test?

Ear Preference for Cell Phone Use Right Ear Left Ear No Preference Right-Handed 436 166 40 Left-Handed 16 50 3