The scoreboard shows the runs of five players of a Jaipur school team. Then Rohit joins and his score is added. By how many runs does the mean score go up?
Class 7Data HandlingData Handling
A18
B3
C9
D6
Step-by-Step Solution
Old mean =5180=36. New mean =6180+54=6234=39. The mean rises by 39−36=3 runs.
Answer: B) 3
Key idea: Mean — the 'fair share'
The **mean** is what each person would get if you redistributed everything evenly. Sum the values, divide by the count.
Example: marks 8, 6, 7, 9, 10. Sum = 40. Count = 5. Mean = 40 ÷ 5 = 8.
Mean is the most common 'average' but it can be pulled up or down by extreme values (one very high or very low number).
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