Statistics
Mean
IIT-JEE PYQ
Grade 11
Question:
The mean of 5 numbers is 18. If one number is excluded, the mean of the remaining 4 numbers becomes 16. The excluded number equals _____.
Step-by-Step Solution
Key Concept: Find the total sum of all 5 numbers and the total sum of the remaining 4 numbers separately (using mean $\times$ count), and subtract one from the other.
The detailed step-by-step mathematical proof is available inside the Mathbee app workspace.
Correct Answer: 26