Question

Given below is a frequency distribution table. read it and answer the questions that follow.

Class interval	Frequency
$$ 10-20 $$	$$ 5 $$
$$ 20-30 $$	$$ 10 $$
$$ 30- 40 $$	$$ 4 $$
$$ 40 -50 $$	$$ 15 $$

$$ 50 -60 \quad \quad \quad 12 $$
(a) What is the lower limit of the second class interval ?
(b) What is the upper limit of the last class interval ?
(c) What is the frequency of the third class ?
(d) Which interval has a frequency of $$ 10 $$?
(e) Which interval has the lowest frequency ?
(f) What is the class size ?

Answer 1

From observing the given frequency table:

(a) Lower limit of second class interval $$ ( 20 -30) $$ is $$ 20 $$

(b) The upper limit of the last class interval $$ ( 50 -60) $$ is $$ 60 .$$

(c) The frequency of the third class $$ ( 30 -40) $$ is $$ 4. $$

(d) The interval $$ ( 20-30) $$ has frequency of $$ 10. $$

(e) The interval $$ ( 30-40) $$has the lowest frequency i,e, $$ 4 $$

(f) $$\text{Class size = upper class limit - lower class limit.}$$, for a class.

Let us take first class i.e. $$ 10-20 $$ from the given classes.

Therefore $$ 20 - 10 = 10 $$ is the class size.