Question

• A. 2
• B. 4
• C. 8
• D. 7

Answer 1

Answer:

C. 8

The value of x is 8

1. Median = 28.5 (lies in class interval 20–30)

2. Lower limit (l) = 20

3. Frequency (f) = 20

4. Preceding cumulative frequency (cf) = 5 + x

5. Total frequency (N) = 52 + x

6. Class height (h) = 10

Formula:
$\text{Median} = l + \left(\frac{\frac{N}{2} - cf}{f}\right) \times h$

$28.5 = 20 + \left(\frac{\frac{52 + x}{2} - (5 + x)}{20}\right) \times 10$

$8.5 = \frac{42 - x}{4}$

$34 = 42 - x$
$x = 42 - 34 = 8$