Q16 of 79 Page 25

The mean of five numbers is 27. If one number is excluded, their mean is 25. Find the excluded number.

The mean of the numbers is 27

The sum of 5 numbers = 5 * 27


= 135


If one number is excluded, then the new mean is 25


Therefore sum of new numbers = 4 * 25


= 100


Therefore, excluded number = 135 – 100


= 35


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