We suspect that, on average, students will score higher on their second attempt at the sat mathematics exam than their first attempt. here are the results for 46 randomly chosen high school students:
-0|176655
-0|144422
0l11222333
0|1555666789
1|100223
1. should we use a z-test or a t-test on this data? why?
a. a z-test because the population standard deviation is unknown, but we have the data to calculate the sample standard deviation
b. a z-test because we know the value of the population standard deviation
c. a t-test because the population standard deviation is unknown, but we have the data to calculate the sample standard deviation
d. a t-test because we know the value of the population standard deviation
2. can we say that the condition of "normality of the population" is met? why or why not?
a. yes, because the plot has no extreme outliers
b. no, because the sample size is too small to apply the central limit theorem
c. yes, because the population of change in scores in normal
d. no, because we do not know if the population of change in scores is normal