Target Exam

CUET

Subject

-- Applied Mathematics - Section B2

Chapter

Question:

If the following data is obtained from a simple random sample:

6, 7, 9, 10, 11, 17

Then the point estimate of population standard deviation is:

Options:

15.21

10

3.898

3.192

Correct Answer:

3.898

Explanation:

The correct answer is Option (1) → 15.21

Data: 6, 7, 9, 10, 11, 17

Sample size: $n=6$

Sample mean:

$\bar{x}=\frac{6+7+9+10+11+17}{6}=\frac{60}{6}=10$

Deviations squared:

$(6-10)^2=16$

$(7-10)^2=9$

$(9-10)^2=1$

$(10-10)^2=0$

$(11-10)^2=1$

$(17-10)^2=49$

Sum: $16+9+1+0+1+49=76$

Sample variance (unbiased):

$s^2=\frac{\sum (x_i-\bar{x})^2}{n-1}=\frac{76}{5}=15.2$

Sample standard deviation (point estimate of population σ):

$s=\sqrt{15.2} \approx 3.90$

Final Answer: The point estimate of population standard deviation = 3.90