Unit 4 · Statistics and Probability
Five Scores — Which Claims Hold?
Lesson 7 of 8
Premium
About this lesson
When a question bundles average, median, and “above average” claims together, compute the average and median first — then test each statement with arithmetic, not guesswork.
Chapters
0:00Introduction
0:21The Question
1:07Finding the mean (average) score
1:39Evaluating Claim 2 (Diana's deviation)
2:05Evaluating Claim 3 (finding the median)
2:40Exam strategy — the deviation balance method
3:25Confirming the final option
Question
Five students' test scores:
| Student | Score |
|---|---|
| Aiden | 68 |
| Bella | 75 |
| Callum | 55 |
| Diana | 82 |
| Emma | 73 |
Three claims:
-
The average score is exactly 70.
-
Diana's score is more than 10 points above the average.
-
The median score is 73.
Which claims are correct?
Free account · Selective
Take your Selective prep further
- Sample questions & worked solutions across core Selective topics
- Digital exam simulator with interactive practice sets
- Personalised progress tracking across all your devices
Already have an account? Log in here
No payment required. Compare Selective plans
Give Your Child the Best Chance at Selective Entry
Join NSW families preparing their children for the Selective Schools Placement Test with the most realistic online Selective practice tests available. First tests free—no credit card required.
Claim Your Free Selective Practice Tests