# What is the value of 3 12

## Mean - mean

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Here's how to find the mean of two or more numbers or quantities.

### The mean of numbers

You can calculate the mean of two or more numbers by adding up all the numbers and dividing the sum by the number of numbers. The mean value is also called the average value or arithmetic mean.
Average of Numbers The coach of a basketball team measures the height of his players. Calculate the average height of all basketball players.
The average height of all basketball players is.
Average value for bar charts The chart shows the number of visitors to the Star Cinema over the course of a week. How many visitors did the cinema have on average in one day?
On average, 550 people visit the Star Cinema every day.

### change in mean value

If you have calculated the mean of two or more numbers and add more numbers, the mean can change.
Adding values ​​without changing the mean value You gave the values ​​6, 2, 15 and 9. The mean value is (6 + 2 + 15 + 9): 4 = 8. Another number should be added without the mean value changing. Since the mean value should not change and there are now 5 numbers, their total must be 8 5 = 40. So you just have to add the mean to the original sum: 8 4 + 8 = 8 5
Adding a value to achieve a desired mean You have given the numbers 2, 7, 14 and 16 and want to add a number so that the mean is 8. Which number do you have to add? First you calculate the sum of the given numbers: 2 + 7+ 14 + 16 = 39 Since the mean of 5 numbers should be 8, their sum is 8 5 = 40. So you have to add 1.
Adding a column in the bar chart when limiting the mean value The operator of the Star Cinema must buy enough drinks for the whole week at the beginning of each week. He calculates that with an average daily turnover of 550 beverages, he can just manage the amount bought. The bar chart shows the beverage sales up to Saturday. How many drinks can he sell on Sunday?
The operator can sell a maximum of 400 drinks on Sunday.