ELI5: Explain Like I'm 5

Population mean

Population mean is a way of describing how much of something the whole population has. Let's say you have 20 people in a room and you want to know how tall they all are on average. To calculate the population mean, you would add up the heights of all 20 people and then divide that number by 20. This will give you an average height or the population mean of all 20 people in the room.