In Mary's first math test she scored 87. The mean and standard ...

[asd123]

In Mary's first math test she scored 87. The mean and standard deviation for the class were 71 and 18 respectively. In her second math test, Mary scored 66. The mean and standard deviation for the class were 53 and 14 respectively.
 
  In which test did Mary do better relative to the rest of the class? Explain your reasoning. (Hint: find the z-scores corresponding to her two test scores.)

Question 2

In a group of 500 men and women, those who smoked did worse on tests of reaction time than those who did not smoke.
 
  A) Designed experiment B) Observational study

[mariahkathleeen]

Answer to Question 1

Relative to the rest of the class, Mary did better in the second test. Her z-score on the first test was 0.89 while her z-score on the second test was 0.93.

Answer to Question 2

B

[asd123]

Great answer, keep it coming

[Mochi]

Thanks for the timely response, appreciate it