In a class of 60 students, mathematics examination was conducted. All the students obtained 20 marks each. What would be the mean and standard deviation of marks in mathematics?
Show Hint
- 1200 and 20
- 120 and 1
- 20 and 0
- 20 and 60
The Correct Option is C
Solution and Explanation
Step 1: Calculate the Mean.
All 60 students scored 20 marks.
Mean \( = \frac{{Sum of all scores}}{{Number of students}} = \frac{60 \times 20}{60} = 20 \)
Step 2: Calculate the Standard Deviation.
Since all students have the same score (20), there is no variation. Standard Deviation \( = 0 \)
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