Question

Convert the following data into grouped frequency table with class interval length of $5$. Find the third interval frequency:
$12,12,11,12,2,3,3,3,4,4,2,2,5,6,7,4,7,8,15,15,20,20$

• A. $2$
• B. $5$
• C. $10$
• D. $4$

Answer 1

The correct option is B $5$

Arrange the data in increasing order: $2,2,2,3,3,3,4,4,4,5,6,7,7,8,11,12,12,12,15,15,20,20$

Form the required frequency distribution table with interval of $5$

Class interval	Frequency
$0-5$	$10$
$6-11$	$5$
$12-17$	$5$
$18-23$	$2$

Arrange the data in order: $2,2,2,3,3,3,4,4,4,5,6,7,7,8,11,12,12,12,15,15,20,20$

So, the third interval frequency is $5$.