Below is the distribution of "more than" type of marks obtained by $50$ students in a $100$ marks examination. Prepare the grouped frequency distribution from that.

Obtained marks	No. of Students
$0$ or more than $0$	$50$
$20$ or more than $20$	$48$
$40$ or more than $40$	$40$
$60$ or more than $60$	$31$
$80$ or more than $80$	$10$

To prepare the grouped frequency distribution,we calculate the frequency for each class interval by subtracting the number of students in the higher range from the lower range.
$1$. For $0-20$: $50 - 48 = 2$
$2$. For $20-40$: $48 - 40 = 8$
$3$. For $40-60$: $40 - 31 = 9$
$4$. For $60-80$: $31 - 10 = 21$
$5$. For $80-100$: Since there are $10$ students who scored $80$ or more,and the total is $50$,the frequency for $80-100$ is $10$.

Marks obtained (Class)	$0-20$	$20-40$	$40-60$	$60-80$	$80-100$
No. of students (Frequency)	$2$	$8$	$9$	$21$	$10$