Question

The Class Marks of a Frequency Distribution are 15, 20, 25, 30, . . .
The Class corresponding to the Class Mark 20 is

(a) 12.5 - 17.5
(b) 17.5 - 22.5
(c) 18.5 - 21.5
(d) 19.5 - 20.5

Answer 1

Answer:

d) 19.5 - 20.5

as it is closest value of 20

proof-

the difference between the terms are 1 so,

half the difference =1/2 = 0.5

add 0.5 to upper limit so 20.5

subtract 0.5 to lower limit so 19.5

Step-by-step explanation:

bhul gye bhai aap Mujhe

Answer 2

Solution :-

Given,

Class Marks of a Frequency Distribution are 15, 20, 25, 30 and so on ...

The Lower Limit of the Class Mark 20 is the Mean of 15 & 20.

So, The Lower Limit = $\Big ( \frac{15 + 20}{2} \Big ) = \Big ( \frac{35}{2} \Big ) = \bold {17.5}$

Similarly,

The Upper Limit of the Class Mark 20 is the Mean of 20 & 25.

So, The Upper Limit = $\Big (\frac{20 + 25}{2} \Big ) = \Big ( \frac{45}{2} \Big ) = \bold {22.5}$

Hence, we can Conclude that 20 is the Class Mark of the Class Interval 17.5 - 22.5

∴ Option B is the Right Answer!