The S.D. of the following frequency distribution is
Class 0-10 10-20 20-30 30-40
$f_{i}$ 1 3 4 2

7.8

No worries! We‘ve got your back. Try BYJU‘S free classes today!

9

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

8.1

No worries! We‘ve got your back. Try BYJU‘S free classes today!

0.9

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A $9$
Class $x_{i}$ $f_{i}$ $u_{i} = \frac{x_{i} - a}{h}$ $f_{i} u_{i}$ $f_{i} u_{i}^{2}$
0-10 5 1 -2 -2 4
10-20 15 3 -1 -3 3
20-30 25 4 0 0 0
30-40 35 2 1 2 2
$N = 10$ $\sum f_{i} u_{i} = - 3$ $\sum f_{i} u_{i}^{2} = 9$
$σ = h \sqrt{\frac{Σ f_{1} u_{1}^{2}}{N} - {(\frac{Σ f_{1} u_{1}}{N})}^{2}}$
$= 10 \sqrt{\frac{9}{10} - {(\frac{- 3}{10})}^{2}} = 9$

Suggest Corrections

Similar questions

Class	0-10	10-20	20-30	30-40
$f_{i}$	1	3	4	2

Class	0-10	10-20	20-30	30-40	40-50
Frequency	5	$x$	15	16	6

x

Class	0-10	10-20	20-30	30-40	40-50
Frequency	$7$	$15$	$13$	$17$	$10$

Class	0-10	10-20	20-30	30-40	40-50
$f$	6	10	13	7	4

f

24

Class	0-10	10-20	20-30	30-40	40-50
Frequency	5	25	f	18	7

Join BYJU'S Learning Program