A multiple-choice test consists of ten questions, each with A-E answers. If you guess the answer to each question, how many questions can you expect to get correct? Also find the standard deviation of the number of questions you can expect to get correct.
A) 1, 1.6
B) 3, 1.3
C) 2, 1.3
D) 1.2, 1.6
E) None of the choices are correct

Question

Quizplus · Accepted Answer

The expected number of correct answers is 2, calculated as 10 questions * 1/5 probability of guessing correctly. The standard deviation is √(10 * 1/5 * 4/5) = 1.3.

A Multiple-Choice Test Consists of Ten Questions, Each with A-E