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.
The key words you should notice when looking at this word problem are “less than.” This means that the order is flipped, so “3 less than k” means “k minus 3.”
