Question

Find the mean of the following frequency table: 

Hint:

The mean for grouped data is obtained using $\bar{x} = \dfrac{\Sigma (f \times x)}{\Sigma f}$.

Answer 1

Step 1: Find class marks (midpoints).
Class marks = 1, 3, 5, 7, 9.

Step 2: Apply the formula for mean.
\[ \bar{x} = \dfrac{\Sigma (f \times x)}{\Sigma f} \] \[ \Sigma f = 1 + 2 + 6 + 8 + 3 = 20 \] \[ \Sigma (f \times x) = (1)(1) + (2)(3) + (6)(5) + (8)(7) + (3)(9) = 1 + 6 + 30 + 56 + 27 = 120 \] \[ \bar{x} = \dfrac{120}{20} = 6 \]
Step 3: Conclusion.
Hence, the mean of the data is approximately 6.