A researchers results are shown below using n 25 observation

A researchers results are shown below using n 25 observations. The 95 percent confidence interval for the slope is: (-3.282, -1.284]. [-4.349, -0.217]. [1.118, 5.026]. [-0.998, +0.998].

Solution

degrees of freedom = 25-2 = 23

alpha = 1 -95% = 0.05

critical probability = 1- alpha/2 = 0.975

tscore (23,0.975) = 1.984

margin of error = 1.984 * 0.99855319 = 1.981

95% confidence interval = (-2.2833659 + 1.981 , -2.2833659 -1.981)

= (-4.349 , -0.217)

hence second option is the correct choice