In a final examination in Statistics the mean marks of a group of 150 students were 78 and the s.d. was `8*0`. In Economics, however, the mean marks were 73 and the s.d. was `7*6`. The variability in the two subjects respectively is

Options

A. `10*3%,10*4%`
B. `9*5%,7*9%`
C. `11*2%,10*1%`
D. none of these

Answer

To find the variability in the two subjects (Statistics and Economics), we can use the standard deviation (s.d.) as a measure of variability. The standard deviation indicates how much the marks deviate from the mean.

### Step-by-Step Solution:

1. **Identify the given data:**
- For Statistics:
- Mean (μ₁) = 78
- Standard Deviation (s.d.₁) = 8
- For Economics:
- Mean (μ₂) = 73
- Standard Deviation (s.d.₂) = 7.6

2. **Calculate the variability for Statistics:**
- The variability in Statistics is represented by its standard deviation, which is 8.

3. **Calculate the variability for Economics:**
- The variability in Economics is represented by its standard deviation, which is 7.6.

4. **Compare the variability:**
- Variability in Statistics = 8
- Variability in Economics = 7.6

5. **Conclusion:**
- The variability in Statistics is greater than that in Economics since 8 > 7.6.

### Final Answer:
- The variability in Statistics is 8, and the variability in Economics is 7.6.

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