A beekeeper measured the length of 400 bees

A beekeeper measured the length of 400 bees and recorded the values in a table. The data includes no repeated values.
I don’t understand why does Greg assume 100 groups?
(https://www.gregmat.com/problems/problem/a-beekeeper-measured-the-length-of-400-bees/)

Well if I arrange the lengths in an ascending order and club 4 of them in the one group
Then we will have 100 groups
Think of the last group:
Percentage of bees they are longer than = 396/400 * 100 = 99
Thus, percentile of the last group = 99
But also, without doing any calculations, I can say that this group was at 99 percentile because there were 99 such groups ahead of them
So, visualizing data in 100 groups makes percentile questions a bit easier

thank you for the response.
But I am still confused about the way he arrived at the solution.
how does visualising this data in 100 groups help us anyway?

Basically the number of values in each percentile group is the same, is kind of what he is going for
And that here there are 4 people in each group
The group thing helps you visualize that