SOLUTION: A continuous random variable X follows the t-distribution with 120 degree of freedom. 1) Find P(X>1.980) 2) Find P(X<-1.289)

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Question 381448: A continuous random variable X follows the t-distribution with 120 degree of freedom.
1) Find P(X>1.980)
2) Find P(X<-1.289)
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Just a suggestion: With a degree of freedom this big, you can already replace the t-distribution with the z-distribution. (The graphs of the density functions are almost identical!) So P(X>1.980) = P(Z>1.980), and P(X<-1.289)= P(Z < -1.289). Try it!