Q11 of 174 Page 577

The mean of 8 numbers is 35. If a number is excluded then the mean is reduced by 3. Find the excluded number.

Mean of 8 numbers = 35


Sum of 8 numbers = 8×35 = 280


New mean = 35-3 = 32


Sum of 7 numbers = 32×7 = 224


Excluded number = sum of 8 numbers – sum of 7 numbers


= 280 – 224 = 56


So, the excluded number is 56.


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