37.2k views
2 votes
Can someone check over my work I’m not quite sure if I did it right.Jane and John took different exams and wanted to compare their test scores. Use Z-scores to decide who did better by finding who had the higher z score. John got an 83 on test A and Jane got an 80 on test B Test A: Mean = 79, SD= 3.5Test B: Mean = 77, SD= 2.5I got 1.14 for John and 0.857 for Jane, so John had the higher z score.

User Shuk
by
7.3k points

1 Answer

5 votes

The z-score can be calculated by the following formula:


z=(x-m)/(\sigma)

Where m is the mean, σ is the standard deviation and x is the actual score.

By replacing John's result (83) for x, 79 for m and 3.5 for σ, we get:


z=(83-79)/(3.5)=1.14

Similarly, for Jane's result on test B:


z=(80-77)/(2.5)=1.2

John's z-score was 1.14 and Jane's z-score was 1.2, then, Jane did better than John

User AHiggins
by
8.4k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories