Question

How does t-statistic differ from z-score? Select one:

Answer 1

Answer:

Option c

Step-by-step explanation:

In Statistics, both t and z tests are used for testing of hypothesis.

Whenever we have sample sizes >30 and when we know population std deviation sigma, we use Z test.

i.e. if sigma is known, we check whether sample size >30 then we use z test

Otherwise if population std deviation is not known, we use t test.  

Even if population std deviation is known, if n <30 we use t test. Both use the same formula for std error.

Hence the correct option is option c.