asked 165k views
4 votes
6. What are the odds of scoring 60% or better on a 20 question

True and False test simply by guessing?

asked
User Ryland
by
8.3k points

1 Answer

2 votes
The odds of scoring 60% or higher are 0.25 or 25.17%.


Each True/False question has 2 options.
12/20 = 0.6 or 60%
So you’d need to get at least 12 correct for a score of 60%.
The probability of getting 1 question correct is 1/2, and this is true of each question on the test.
In the formula, N = total number of items in the test; x = number of choices per item; C = number of correct responses. You want to find P(x >= 12), which is to score 60 percent or higher. The probability of getting 12 or more questions on the test correct.

The probability of getting 12 or more correct out of 20 questions by chance with 2 choices per item = 25.1722%.
answered
User Suat
by
7.7k points
Welcome to Qamnty — a place to ask, share, and grow together. Join our community and get real answers from real people.