The Mean is the total of the values in the data, divided by the number of values.
In a example, the mean of the numbers 3, 5, 6, 9, 13 and 15 is:
(3 + 5 + 6 + 9 + 13 + 15) ÷ 6 = 8.5
(Note the use of brackets to follow BIDMAS rules. If you are using a calculator, make sure that you use the brackets).
Five trays contained strawberries. The number of strawberries in each tray was recorded as 24, 24, 24, 24, 29.
What was the mean number of strawberries in each tray?
Total number of strawberries
= 24 + 24 + 24 + 24 + 29
= 125
Number of trays = 5
Mean number of strawberries = 125 ÷ 5 = 25
Answer: 25
A group of 6 friends collect game cards. The mean number of game cards that they have is 12. One of the friends leaves, and the mean number of game cards is now 11. How many cards did the friend who left have?
Total number of cards for all 6 players is 6 x 12 = 72.
Number of cards when there are 5 players is 5 x 11 = 55.
Cards owned by leaver = 72 - 55 = 17
Answer: 17