The lifetimes of 100 light bulbs are tabulated below- Find the modal lifetime- nbsp- nbsp- nbsp- nbsp- Lifetime -in hours- amp- Frequency- nbsp- nbsp- nbsp- 0-20 nbsp- nbsp- nbsp- nbsp- amp- 7 nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- 20-40 nbsp- nbsp- nbsp- nbsp- amp- 13 nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- 40-60 nbsp- nbsp- nbsp- nbsp- amp- 20 nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- 60-80 nbsp- nbsp- nbsp- amp- 18 nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- 80-100 nbsp- nbsp- nbsp- amp- 16 nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- 100-120 nbsp- nbsp- nbsp- amp- 10 nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- 120-140 nbsp- nbsp- nbsp- nbsp- amp- 7 nbsp- nbsp- nbsp- nbsp- 140-160 nbsp- nbsp- nbsp- amp- 9 nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- nbsp- - nbsp-70 hours72 hours58 hours84 hours

459

You visited us 459 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XI

Statistics

Mode of Continuous Series

The lifetimes...

Question

The lifetimes of 100 light bulbs are tabulated below. Find the modal lifetime.

$\begin{matrix} L i f e t i m e (i n h o u r s) & F r e q u e n c y 0 - 20 & 7 20 - 40 & 13 40 - 60 & 20 60 - 80 & 18 80 - 100 & 16 100 - 120 & 10 120 - 140 & 7 140 - 160 & 9 \end{matrix}$

70 hours

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

72 hours

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

58 hours

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

84 hours

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

Open in App

Solution

The correct option is A 70 hours
The grouping and analysis table for the distribution is given below

From the analysis table, the class 60-80
has the maximum score. Hence, 60 - 80 is
the modal class.

Here, $L = 60; D_{1} = 20 - 18 = 2$
$D_{2} = 18 - 16 = 2; h = 20$
$M o d e = L + \frac{D_{1}}{D_{1} + D_{2}} \times h = 60 + \frac{2}{2 + 2} \times 20 = 70 h o u r s$

Suggest Corrections

Similar questions

Question 2
The following data gives the information on the observed lifetimes (in hours) of 225 electrical components:

$\begin{matrix} Lifetimes(in hours) & 0 - 20 & 20 - 40 & 40 - 60 & 60 - 80 & 80 - 100 & 100 - 120 Frequency & 10 & 35 & 52 & 61 & 38 & 29 \end{matrix}$

Determine the modal lifetimes of the components.

Q. Make a frequency curve of the following data:

Class-interval	20−40	40−60	60−80	80−100	100−120	120−140	140−160
Frequency	3	7	11	15	13	6	2

The following data gives the information on the observed lifetimes (in hours) of 225 electrical components:

Lifetimes (in hours)	0 − 20	20 − 40	40 − 60	60 − 80	80 − 100	100 − 120
Frequency	10	35	52	61	38	29

Determine the modal lifetimes of the components.

Q. Compute the mean of the following frequency distribution:

Class	0 − 20	20 − 40	40 − 60	60 − 80	80 − 100	100 – 120	120 – 140
Frequency	6	8	10	12	6	5	3

Q. Find the median of the following data:

Class interval	$0 - 20$	$20 - 40$	$40 - 60$	$60 - 80$	$80 - 100$	$100 - 120$	$120 - 140$
Frequency	$6$	$8$	$10$	$12$	$6$	$5$	$3$

Join BYJU'S Learning Program

The lifetimes of 100 light bulbs are tabulated below. Find the modal lifetime. Lifetime(in hours)Frequency0−20720−401340−602060−801880−10016100−12010120−1407140−1609

The correct option is A 70 hoursThe grouping and analysis table for the distribution is given below From the analysis table, the class 60-80 has the maximum score. Hence, 60 - 80 is the modal class. Here, L=60;D1=20−18=2 D2=18−16=2;h=20 Mode=L+D1D1+D2×h=60+22+2×20=70 hours

The lifetimes of 100 light bulbs are tabulated below. Find the modal lifetime.

$\begin{matrix} L i f e t i m e (i n h o u r s) & F r e q u e n c y 0 - 20 & 7 20 - 40 & 13 40 - 60 & 20 60 - 80 & 18 80 - 100 & 16 100 - 120 & 10 120 - 140 & 7 140 - 160 & 9 \end{matrix}$