If the mean of 5 numbers is 20, and a sixth number 26 is added, what is the new mean?
Answer and explanation
Correct answer: B. 21
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- Step 1: Calculate the sum of the original numbers from the given mean :
- Step 2: Add the sixth number to obtain the new total sum :
- Step 3: Divide the new sum by the new total count of numbers :
Answer
21.
Why not the others: The values 22, 20.5, and 23 arise from dividing by 5 instead of 6 or incorrectly averaging the means directly.
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