Twenty numbers in five rounds, easy to hard, each with four lines of arithmetic, like ? = 56 over 6 × 9, 7 × 8, 5 × 11 and 8 × 6. 20 seconds each, one life. Pick the line that makes the number; every problem you clear is a point. Keys 1 to 4 answer. The clock starts when you do.
About Back
Back is a free daily mental math game from Mind Loft: Blitz played backwards. Every one of its twenty problems gives you a number, like ? = 56, and four lines of arithmetic, and exactly one of the lines makes it. The lines climb through five rounds, from single sums and the times tables up to brackets, squares, percentages, roots and two-digit products. You get twenty seconds each and one life, so your score is how far up the ladder you got before a wrong answer or an empty clock stopped you.
The four lines in a problem always share one shape, so the answer cannot be spotted by its length or its signs: every line has to be worked. The wrong lines are chosen to come close. Some only make the number if you read them left to right or ignore a bracket; some end in the same digit; the rest are one or two off. There is no way through but the arithmetic, and the order you do it in.
Everyone plays the same twenty problems in the same order each day, so the daily leaderboard is a straight fight: furthest wins, and ties break by time. Twenty new problems drop every day at midnight Eastern. No app, no signup, play free in your browser, keep a streak, and race the daily leaderboard. It is one fifth of the Math Gauntlet, with Blitz, Blitzed, Gap and Series.
Back, in short
How do you play Back?
Each problem gives a number, like ? = 56, and four lines of arithmetic of the same shape; exactly one makes it. Twenty climb from the times tables to brackets, squares and two-digit products, twenty seconds each, and one wrong answer ends the run.
Is Back free to play?
Yes. Back is free to play in your browser on Mind Loft, with no app to install and no account required.
When does a new Back puzzle come out?
A new Back arrives every day at midnight Eastern time.
What kind of puzzle is Back?
Back is a daily number puzzle from Mind Loft: which line makes it. Puzzle type: reverse mental math. It is part of the daily number puzzles lineup.
Can I play past Back puzzles?
Yes. Every past Back board is in the puzzle archive, a tap away by day.
What other daily number puzzles does Mind Loft have?