Question

Use the calculator provided to solve the following problems. Consider a t distribution with 16 degrees of freedom. Compute P ≥ t 1.43 . Round your answer to at least three decimal places. Consider a t distribution with 12 degrees of freedom. Find the value of c such that = P < − c < t c 0.95 . Round your answer to at least three decimal places.

Answer 1

In the first question, we need to find the area under the t distribution that is right to t= 1.43. On calculator, Press 2nd - > Vars. Select tcdf and enter data as follow and press enter:

Second line in the above screen shows the output.

In the command, tcdf, 1000 shows that we need area from 1.43 to infinity.

Answer: 0.0860

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Here we need t=c that has 1- ((1-0.95) /2 ) = 0.975 area to its left.

Press 2nd - > Vars. Select invT and enter data as follow and press enter:

Using invT(0.975, 12) function the value of t that has 0.975 area to its left is 2.179.

Answer: c= 2.179