When we use Z-test and T-test:-
When population standard deviation () is known, then we use Z- test and if population standard deviation () is unknown, then we use t- test.
Answers.
1. You should use one sample t test because here mean () is given but population standard deviation () is unknown.
2. You should use One sample Z- test because here mean () is given but population standard deviation () is also known.
3. You should use One sample Z- test because here mean () is given but population standard deviation () is also known.
6. You should use One sample Z- test because here mean () is given but population standard deviation () is also known.
7. You should use one sample t test because here mean () is given but population standard deviation () is unknown.
8. You should use one sample t test beause here mean () is given but population standard deviation () is unknown.
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