Remember a briefly displayed random equation, then answer at your own pace. Choose any of four operations and advance through endless stages, with up to three digits and a 1-second display.
Remember a briefly displayed equation and solve it. Choose addition, subtraction, multiplication and division. Numbers grow to three digits and display time falls from 3 to 1 second as stages continue.
Controls
Show the equation, remember it, then enter an integer after it disappears.
Use ± for negative answers. A correct answer unlocks the next stage.
Playing tips
Compare the numbers before subtracting; think of multiplication when dividing.
Common questions
Must I answer before the equation disappears?
No. Take as long as you need after it disappears. Division always gives an integer, and multiplication never uses zero.
Can I resume later?
Your equation, remaining display time and answer save. Resume the same challenge when ready.