Yes 8.54 as rational number because in can be written as 854/100
The solution step by step. 43 comes from adding all the given numbers together.
Answer:
Option (B) is the correct answer to the following question.
Step-by-step explanation:
Step-1: We have to find the Mean of the series.
The series is Given in the question 62 61 61 57 61 54 59 58 59 69 60 67.

Step-2: We have to find the Standard Deviation.
Let Standard Deviation be x.
Formula of Standard Deviation is: 
Put value in formula of Standard Deviation,
= 40.75
Step-3: Then, we have to find the critical value by chi-square.


Then, find the confidence interval which is 95%.


T= sqrt(5/wc)
remove ( )
T= 5sqrt/wc
multiply by wc
Twc=5sqrt
divide by Tc
W= 5sqrt/cT
hope this helps