Mental math sprint
Mental arithmetic is not about being fast at the method you learned on paper. It is about picking an easier route to the same answer, and there are only a handful of routes worth knowing.
What you'll learn
11 chapters, then the quiz
- 01Why botherThe point is judgement, not showing off.
- 02Splitting numbersBreak one factor into friendly pieces.
- 03Rounding and compensatingMove to a round number, then correct.
- 04Doubling and halvingMove a factor of two across the multiplication.
- 05Shortcuts worth knowingNine, eleven, five and twenty five.
- 06PercentagesEverything is built from ten percent.
- 07Fractions and decimalsSwapping between the two forms.
- 08Squares and rootsA short list that pays for itself.
- 09DivisionFactor the divisor into easy steps.
- 10Estimation and checksGetting close on purpose.
- 11Building speedHow to get quicker without drilling for hours.
More math & logic tests
See all →- Hard
Logic puzzles
Short problems where the obvious answer is usually the wrong one.
7 questions9 min - Medium
Probability basics
Coins, dice and cards, plus the traps that come with them.
7 questions7 min - Medium
Algebra fundamentals
Rearranging, solving and reading what an equation is telling you.
8 questions7 min