Histograms, a mistake in a video lecture

In this video, the instructor says integrals are going within the same range of numbers each time through and there are 4 numbers in each range.

But it seems to me that he is making a mistake, isn’t he?

0-3: 0, 1, 2, 3 (four numbers)
4-8: 4, 5, 6, 7 , 8 (five numbers)

and it goes on with 5 numbers until 23-27.

Am I missing something or is he wrong?

Between: 00:05 and 00:50

Yeah, you’re right. He also counts 18 twice.

This said, it’s not strictly necessary for a histogram to have each bin correspond to the same interval. It might be useful when you present your data to have a bin corresponding to a single special value — for example, maybe you want to point out the number of people who have never been on a roller coaster.

Yep, Video Lecture Guy is wrong. I guess you can’t trust everything you see on YouTube.

ETA: Why are comments disabled on that video? Is he afraid that someone will point out his mistakes?