Query about Question 17 from "PrepSwift Quant Tickbox Quiz #1 (Arithmetic Column 1)" [6367]

https://prepswift.gregmat.com/quizzes/quiz/prepswift-quant-tickbox-quiz-1-arithmetic-column-1 (Question 17)


Why is it that when we find out the interval (133 to 199) has 67 numbers in it — which is an odd number — we divide by 2 and don’t account for the odd one out in the answer?