# The following data represent the muzzle velocity ( in feet per second ) of shells fired from a 155 mm gun For each shell two measurements of the velocity were recorded using two different measuring devices resulting in the following data Observation

The following data represent the muzzle velocity ( in feet per second ) of shells fired from a 155 mm gun For each shell two measurements of the velocity were recorded using two

different measuring devices resulting in the following data

Observation

6

794 5 793.8 790.3 790. 6 790.6 791.4

8009 7925 800 2 796.1 795.5 787 6

( a ) Why are these matched – pairs data ?

. A . Two measurements ( A and B ) are taken on the same found .

B . The measurements ( A and B ) are taken by the same instrument .

C . All the measurements came from rounds fired from the same gun

D . The same round was fired in every trial

( b ) Is there a difference in the measurement of the muzzle velocity between device A and device ! at the a – 0 09 level of significance ? Note : A normal probability plot and boxplot of

the data indicate that the differences are approximately normally distributed with no outliers What is your conclusion regarding Ho ?

PROGRAM

Do not reject H

Reject He

10 ) Construct a 98’s confidence interval about the population mean diference . Compute the difference

vice A minus device B . Interpret your results

B interpret your

The confidence interval is (If

Round to three decimal places as needed

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