Unit 2 · Number Theory
6 Players Each vs Each — How Many Matches?
Lesson 15 of 15
Premium
About this lesson
Six children each play every other child once in a tennis tournament. How many matches in total? The trick: if you just multiply 6 × 5 = 30, you count every match twice (A vs B AND B vs A). You must divide by 2 to avoid double-counting.
Chapters
0:00Introduction
0:22The Question
0:52Modelling the first few children
1:27Completing the combination pattern
1:48Calculating the total & final selection
2:08Strategic exam tip
2:45Correct answer
Question
Six children are going to play in a tennis tournament.
Each child will play every other child once.
How many matches will there be in total?
Free account · OC
Take your OC prep further
- Sample questions & worked solutions across core OC 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 OC plans
Give Your Child the Best Chance at OC Entry
Join NSW families preparing their children for the Opportunity Class Placement Test with the most realistic online OC practice tests available. First tests free—no credit card required.
Claim Your Free OC Practice Tests