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# Example finding critical t value

Given a confidence level, we can calculate a critical value (t*) in a t-distribution with n-1 degrees of freedom.

## Want to join the conversation?

• I believe that Sal accidentally selected the wrong option at the end: instead of 2.624, he chooses 2.264.
• On my calculator I input the information of the confidence level and the degrees of freedom and the value I got was 2.264. Is the table there wrong, or was my calculator wrong because I put df as 14 and C level as 0.98.
• It's worth noting this is a 'two-tailed T-distribution', some T-distribution tables are one tailed. In that scenario the Tail probability is simply 1 - the confidence level.
• I have a question....why is CC only in Bulgarian?
• Huh... for me I can see closed captions in English, it also says that English is the default language. But other than that, I don't know why it's not there in any languages other than English and Bulgarian
(1 vote)
• Please fix the Bulgarian-->English translation issue so the English reads correctly. Also cute mistake at (2.264/2.624) I also made this mistake at first.
• Could anyone please tell me, where are we gonna study about degrees of freedom (D.F) in-depth ?

• before calculations, do we need to first check the conditions needed for using a t-test? ie random, Normal and independence
(1 vote)
• I think it is needed, but in this question, we don't have to check these conditions because we do not have a choice about that. eg,It is impposible to find a critical t value, for the conditions are not satisfied.
• Does anyone know where I can invT in TI-83 calculator? I couldn't seem to find it.
• I'm using a Ti-84, so I have no idea whether it's going to be different for a 83 but:
press 2nd > vars(dist). It should be under the distribution tab.
(1 vote)
• You can just google t-value table and it should be there. You can take a screenshot of it or save it to your computer.
(1 vote)
• Find the value of t for student's distribution that satisfy the following condition: the combined area to the right of t and the left of -t is 0.01 and v=5?
(1 vote)
• How do I do this on a Ti-84?
(1 vote)