Question

Draw less than and more than Ogives for the following frequency distribution.

Scores	Frequency
$20-30$	$4$
$30-40$	$6$
$40-50$	$12$
$50-60$	$8$
$60-70$	$10$
$70-80$	$14$
$80-90$	$2$
$90-100$	$4$

Answer 1

Step 1: Make the required frequency distribution table.

Construct Table for “less than” and “more than” cumulative frequencies.

For less than Ogive		For more than Ogive
Scores	Frequency	Scores	Frequency
Less than $30$	$4$	More than $20$	$60$
Less than $40$	$10$	More than $30$	$56$
Less than $50$	$22$	More than $40$	$50$
Less than $60$	$30$	More than $50$	$38$
Less than $70$	$40$	More than $60$	$30$
Less than $80$	$54$	More than $70$	$20$
Less than $90$	$56$	More than $80$	$26$
Less than $100$	$60$	More than $90$	$4$

Step 2: Draw the Ogive Curves.

From above frequency distribution table

Plot the ‘less than’ and ‘more than’ Ogives on the same graph. i.e., plot the two curves on the same graph as shown: