Question

If the probability of writing the correct answer to the question on an exam is 2/5, what are the odds against writing the correct answer?

Answer 1

Answer is  3:2

Explanation

The probability of getting the correct answer is 2/5. This means there are 2 events of getting it right out of 5 events total. Since there are 2 events of getting it right, there are 5-2 = 3 events of getting it wrong.

The odds against getting the right answer is 3:2. We list the number of ways to get it wrong first, a colon, then the number of ways of getting it right.