Number challenges
Four different number problems. Work each one through at your own pace, with hints when you want them.
Choose a level
Each round has one multiplication, one digit reversal, one cube root and one prime factor problem. Work through the method after each answer.
Smaller values and direct clues. Use careful reasoning you can build on.
- 4questions, one of each kind
- 3optional hints per question
- ∞no deadline or speed score
Example
128 × 12 = ?
Try a short method first. The full working appears after you answer.
Hints and Quick working do not change your score. Showing an answer gives 0 points for that question.
Hints
Start with your own idea, or open one step at a time.
Worked solution
Four questions done.
0 of 4correct
Review your questions
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How this practice works
Each round has four different number problems and no deadline. You can use Quick working and up to three hints per question.
Enter a whole number and press Enter or choose Check answer. A correct answer earns one point; hints do not change the score. Showing the answer earns no point for that question.
After each answer, review the method and check. Finishing all four questions saves the round in your practice history. Ending early does not save it.
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Optional and off by default. Share starts, completions, replays and error categories. For visits from ChatGPT, starts and completions can also include the first QuickenBrain page and broad country. No answers, drawings or names.
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