Question

the following data gives the information on the observed life time in hours of 150 electrical components. life time in hours :0—20 ,20—40,40—60,60—80 ,80—100 frequency 15 10 35 50 70 no samp pls help me by solving step by step pls ​

Answer 1

Step-by-step explanation:

Here , frequency of class interval 60−80 is maximum.

So, it is the modal class

Now, l= Lower limit of modal class =60

f1= Frequency of modal class =61

f0= Frequency of class preceding the modal class =52

f2= Frequency of class succeeding the modal class =38

h= Class interval width = 20

So, Mode =l+(2f1−f0−f2f1−f0)×h

=60+(2(61)−52−3861−52)×20

=60+(122−909)×20

=60+(329)×20

=60+5.625

Mode =65.625

Therefore, modal lifetime of electrical components is 65.625 hours