Question

Consider the following frequency distribution :

Class:	0-5	6-11	12-17	18-23	24-29
Frequency:	13	10	15	8	11

The upper limit of the median class is 

Options

• 17

•   17.5   

• 18

• 18.5

Answer 1

The given classes in the table are non-continuous. So, we first make the classes continuous by adding 0.5 to the upper limit and subtracting 0.5 from the lower limit in each class. 

Class	Frequency	Cumulative Frequency
0.5–5.5	13	13
5.5–11.5	10	23
11.5–17.5	15	38
17.5–23.5	8	46
23.5–29.5	11	57

Now, from the table we see that N = 57.
So, 

\[\frac{N}{2} = \frac{57}{2} = 28 . 5\]

28.5 lies in the class 11.5–17.5.
The upper limit of the interval 11.5–17.5 is 17.5. 
Hence, the correct answer is option (b).