Question

Refer to the accompanying data display that results from a sample of airport data speeds in Mbps. Complete parts​ (a) through​ (c) below. a. What is the number of degrees of freedom that should be used for finding the critical value tα/2​? df= ​(Type a whole​ number.) b. Find the critical value corresponding to a​ 95% confidence level. ta/2 ​(Round to two decimal places as​ needed.) c. Give a brief general description of the number of degrees of freedom.

TInterval

​(13.046,22.15) x =17.598 Sx=16.01712719 n=50

Answer 1

a)

Degrees of freedom(df)=n-1

   =50-1

   =49

b)

from t table to find critical value for alpha= 5% with df= 49

t-critical = 2.01

c)

The number of degrees of freedom for a sample data is number of sample vaules which are determnied after certain restrictions have imposed on all the data vaules.