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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