Answer: 59.342
Step-by-step explanation:
The chi-square critical values are used to find the confidence interval for σ.
Left critical value =
[i.e. chi-square value from chi-square table corresponding to degree of freedom n-1 and significance level of
]
To find : left critical value for 95% confidence interval for σ with n = 41.
Significance level : 
degree of freedom = 41-1=40
Now, the left critical value for 95% confidence interval for σ with n = 41 is the chi-square value corresponding to degree of freedom n-1 and 
=59.342 [from chi-square table ]
The answer to your question is 14:9
Plug in 2.5 for x and you get
2.5+1 which equals 3.5
Not sure why it needs to be a fraction, if I am missing something please tell me. 64 or 64/1