The sprint flips the board format on its head: 20 mixed problems, but only one on screen at a time, and you must clear the current one to see the next. The score is always a full clear — what's measured is how fast you get there.
This Easy tier uses the same friendly ranges as the practice boards — times-table facts like "9 × 6" and two-digit sums like "48 + 27" — so the challenge is pure tempo, not difficulty. It's the right entry point before Medium and Hard raise the numbers on you.
How to play
Problems come one at a time, in order — no skipping ahead.
Type the answer; an exact match commits instantly and the next problem appears. Enter is optional.
A wrong answer on Enter shakes the box and clears it — no penalty, just lost seconds.
The clock counts up from your first keystroke; there is no time limit. Your finish time is the score.
Give up ends the run early and shows your results.
What counts in this quiz
20 problems per sprint, each randomly one of +, −, × or ÷ at easy ranges.
Additions use numbers 12–89, subtractions stay under 100 with positive answers, multiplication is tables to 12 × 12, division is always exact with divisors 2–9.
Unlike the boards, answers can repeat between problems — you only ever face one at a time, so it doesn't matter.
Good to know
In 1980 Shakuntala Devi multiplied two randomly chosen 13-digit numbers in her head in 28 seconds — a Guinness World Record.
Fast mental adders usually work left to right — hundreds first, then tens, then ones — the reverse of how it's taught on paper.