About Math Trainer

Math Trainer is free web app for practicing mental arithmetic.

How It Works

There are 100 levels which range in difficulty from beginner to expert. You advance levels by answering a series of problems, not more than ten, within a given time limit. The time limit for a round depends on the difficulty and number of the questions.

When you advance a level, your progress is saved in the browser you are using. This allows you to return later and pick up where you left off.

Every question has an acceptable duration associated with it. Some factors that determine this duration are the number of mental computations necessary to solve the problem, whether carrying or borrowing is required, the number of digits in the answer, and so on. There is also a growing database of users' empirical performance which will be used to refine the acceptable duration for every question.

The time limit for a round of questions is the sum of the acceptable durations. Therefore you can miss one question's time allowance and still advance if you make up the time on other questions.

The acceptable duration for a question does not depend on the level of the user. A question may appear on more than one level, but the likelihood it will appear will be different. The purpose is to solve increasingly difficult mental math problems in an acceptable amount of time, rather than to achieve ever-faster performance on easier problems.


Why is there no Enter button?

The user interface works by automatically advancing when the correct answer is input. Therefore there is no penalty for wrong answers, so guessing can be abused, but less so at higher levels. You're unlikely to guess the right answer for large numbers.

Why didn't you do multiple choice?

Many mental math apps employ multiple choice to minimize the need for user input. However, there's no way to prevent a user from using process of elimination, which is really a different skill.

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