Transum Software

One Minute Maths

Mental Arithmetic Speed Calculations.

This is challenge number 1. You can earn a trophy if you complete all five challenges.

How quickly can you do some simple additions? Click the button below to test yourself.


Type your final answer into the box above then press the button. Or you could Start Again.

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Instructions

Without using a calculator or writing anything down you are challenged to do the calculations in your head.

There are five multi-step calculations and you have a minute to do each one. If you can do all five you will be awarded a trophy.

Good Luck!

The calculations have been chosen carefully. They are sums that have caught many people out in the past. Even adults have got the answers wrong so think carefully and don't be put off if you get them wrong first time.

The reason it is easy to make a mistake is because each calculation includes a 'carry'. If you do the calculation on paper you will see that when adding up one of the columns of digits the total is ten. This involves adding one to the next column to the left and when trying to do this in your head it is easy to put that one in the wrong column.

Answers

The solutions to this and other Transum puzzles, exercises and activities are available in this space when you are signed in to your Transum subscription account. If you do not yet have an account and you are a teacher or parent you can apply for one here.

A Transum subscription also gives you access to the "Class Admin" student management system and opens up ad-free access to the Transum website for you and your pupils.

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More Activities

If you would like more practice have a look at the Place Value or Mental Methods topic pages.

Classic Mistake!

Aha! You have made the same mistake that so many other people have made. The answer is not 2000. We though we might catch you out so don't be worried.

If you do the calculation with pencil and paper you should be able to see that you have carried one into the wrong column.

30
1000
40
20
+ 10


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