Counting combinations
Decide what makes two outcomes different.
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Example
Example
Example · Standard
Available: A, B, C, D · Positions: 3
Order does not matter · No repeats
Explore the idea
- Possible outcomes
- 10
Change the rules and compare the possible selections.
Arrange items or choose groups
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6 questions · No time limit
- Questions answered
- 0 / 6
- Active time
- 0:00
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Check whether order matters and whether repeats are allowed, then count the outcomes.
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Reload pageExplore the method
Separate an ordered arrangement from a group that contains the same items.
On by default unless you turn it off. Saved choices are kept. Shares starts, completions, replays and error categories. For ChatGPT visits, starts and completions may include the first QuickenBrain page and country. No answers, drawings or names.
How this data is usedHelp
For independent choices, pair every option in the first choice with every option in the second. Arrangements count different orders separately; selections count each group once. Codes may repeat symbols. Grid routes use only the stated right and down moves.
Each round has six questions and no time limit. Choosing an answer locks it. Review the steps, then move to the next question. Finish all six to save the round. Active time includes reviewing the steps, but does not count time when this page is hidden. Speed does not affect your score.
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Original practice puzzles, not a standardized assessment.
About this practice
Learn a method
Decide whether order mattersDecide what makes two outcomes different.
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On by default unless you turn it off. Saved choices are kept. Shares starts, completions, replays and error categories. For ChatGPT visits, starts and completions may include the first QuickenBrain page and country. No answers, drawings or names.
How this data is used