Question

The mean of 10 numbers is 20. If 5 is subtracted from every number, what will be the new mean?

Answer:

The new mean will be 15.

As we know the mean of 10 numbers is 20, the sum of the 10 numbers is 20*10=200. If 5 is subtracted from each number the new total would be 200-(10*5)=200-50=150 and hence, the new mean will be 150/10=15.


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