Take all the numbers used and add them all up, then divide by the number of numbers there are. This will give you the mean or average of the numbers.
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There are 512 subsets in 123456789. This is because there are 9 elements. Take 2, and make it to the 9th power, this is 512, so there are 512 subsets.
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1. Write down the set of numbers to be averaged. 2. Add the set of numbers together and total. Write down the answer. 3. Count the amount of numbers in the set. 4. Divide the total
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