What does mean, median and mode mean?

Mean: Fancy word for the "average". Add all of the numbers up and divide by how many numbers there are

Example: Say you have the numbers 3, 4, 6 and 7. Add all of them up to get 20. Since we started with 4 numbers, you do 20 / 4 = 5. The average of those four numbers is 5

Median: This one is weird. Basically, you have to line all the numbers up from least to greatest, and then count to the middle.

Example: Say you have the numbers 3, 7, 3, 4, 5, 2, 4
First, line them up from least to greatest: 2, 3, 3, 4, 4, 5, 7
Then count to the middle of the 7 numbers
4 is in the middle (there are three numbers before and after it), so 4 is the median

Sidenote: if you have an even number of numbers, like 2, 2, 3, 3, you go in the middle and say 2.5

Mode: This one is pretty easy. Mode is basically the number that is most common in a set of numbers

Example: Say you have the numbers 3, 3, 3, 3, 4, 5, 5, 8, 8, 8,
There are four 3's, three 8's, two 5's, and one 4
3 occurs the most amount of times so it is the mode.

I hope that makes sense.