Mean is a measure of central tendency. It is the sum of a set of values divided by the number of values in a set. In other words add up all the numbers and divide the result by how many numbers there are.
Therefor the mean is 5.
Median is also a measure of central tendency. It is the middle number in a set of data after the data have been arranged in order.
The median is 3.
This is how you get the median if you have 2 numbers in the middle:
-Add the 2 numbers and divide the sum by 2.
The median is 3.5