Question: On a true-false test with multiple items, is “True” the correct answer on half the questions? Tests from several disciplines were studied. The result below for 90 items is typical.

Ninety Items Classified by Correct Answer

(a) What is the expected number of “True” and “False” correct answers if development of True/False items is random with regard to the correct outcome for a particular item?

(b) What is the correct null hypothesis here in both written and symbolic format?

(c) What is the value of χ2 for this study?

(d) If alpha = .05, is the null rejected (include critical value with answer)?