SOLUTION: The t-distribution must be used when the sample size is greater than 30 and the variable is normally or approximately normally distributed. True False

Question 1041535: The t-distribution must be used when the sample size is greater than 30 and the variable is normally or approximately normally distributed.
True
False
Found 2 solutions by Edwin McCravy, Boreal:
Answer by Edwin McCravy(20063) (Show Source): You can put this solution on YOUR website!
False. "greater" should be "less"
Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
False. I don't like the question, because 30 is somehow considered magical.
Nevertheless, given the information above, with a normal distribution, people will use a z-test with a sample size greater than 30. The t-test is reserved for sample sizes less than 30, which is why t-tables are structured the way they are. At n=30, there is about 4% error; at n=60 about 2% error, and at n=100 about 1% error.
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