Q15 of 174 Page 571

The mean of six numbers is 23. If one of the numbers is excluded, the mean of the remaining numbers is 20. Find the excluded number.

Given,


Mean of 6 numbers = 23


Sum of numbers = 23 × 6 = 138


Mean of 5 numbers = 20 (Given)


Sum of 5 numbers = 20 × 5 = 100


So,


The excluded number = Sum of 6 numbers – Sum of 5 numbers = 138 – 100 = 38.


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