Is there a way to solve this on a Ti84 What is the value of

Is there a way to solve this on a Ti-84?

What is the value of A such that P(-A < T < A) = .90 for a T random variable with 16 degrees of freedom? Answer to three decimal places. Use Table II from the back of the text.

Solution

You can use the invT function in the ti-84, but you have to set it up first.

invT needs the (left tailed area, degrees of freedom).

Here, the left tailed area of -A is (1-0.90)/2 = 0.05.

Thus, here, you can get -t using

invT(0.05, 16)

So,

-A = -1.745883676

So,

A = 1.745883676 [ANSWER]