Transum Software

Decimal Plus

Practise mental and written methods for adding and subtracting decimal numbers.

Level 1 Level 2 Level 3 Level 4 Description Help More Decimals

This is level 4; Real life problems involving the addition and subtraction of decimal numbers. You can earn a trophy if you get at least 7 questions correct.

At an amusement park a minature train consists of an engine, 3.9 metres long, and one coach, 5.7 metres long. How long is the train altogether?

Working:

mCorrect Wrong
Judy has to travel 4.9 kilometers to get to her school. She has a lift in her auntie's car for 3.7 kilometres then walks the rest of the way. How far does she walk?

Working:

kmCorrect Wrong
A candle is 8.5cm tall when new. One evening it burns down 4.9cm. How tall is it now?

Working:

cmCorrect Wrong
Three toy building blocks are placed end to end. What is the total length of the line of three blocks if their lengths are as shown in the following diagram?

8.5cm
9.1cm
10.5cm

Working:

cmCorrect Wrong
What is the difference between 8.05 and 3.29?

Working:

Correct Wrong
What is the sum of 8.23, 1.19 and 28.9?

Working:

Correct Wrong
Add 69.2 to 31.3 and then subtract 1.91?

Working:

Correct Wrong
What change would you get from £10 if you spent £9.86? Give your answer in pence

Working:

pCorrect Wrong
The range of a set of numbers is found by subtracting the smallest number from the largest. What is the range of the following set of numbers?

{11, 1.1, 1.01, 1.11, 1.101}

Working:

Correct Wrong
This is a magic square. The sum of each row, column and diagonal of three numbers is the same.

16.412.332.8
36.920.54.1
8.228.7?

What is the missing number?

Working:

Correct Wrong
Check

This is Decimal Plus level 4. You can also try:
Level 1 Level 2 Level 3

There is also an exercise on multiplication and division of decimals called Decimal Times.

Instructions

Try your best to answer the questions above. Type your answers into the boxes provided leaving no spaces. As you work through the exercise regularly click the "check" button. If you have any wrong answers, do your best to do corrections but if there is anything you don't understand, please ask your teacher for help.

When you have got all of the questions correct you may want to print out this page and paste it into your exercise book. If you keep your work in an ePortfolio you could take a screen shot of your answers and paste that into your Maths file.

Why am I learning this?

Mathematicians are not the people who find Maths easy; they are the people who enjoy how mystifying, puzzling and hard it is. Are you a mathematician?

Comment recorded on the 3 October 'Starter of the Day' page by Mrs Johnstone, 7Je:

"I think this is a brilliant website as all the students enjoy doing the puzzles and it is a brilliant way to start a lesson."

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"My Primary 7 class in Mercy Primary school, Belfast, look forward to your mental maths starters every morning. The variety of material is interesting and exciting and always engages the teacher and pupils. Keep them coming please."

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Snooker Investigation

Given the width and height of a snooker table can you predict which pocket the ball will end up in and how many times will it bounce off one of the sides?

Answers

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Go Maths

Learning and understanding Mathematics, at every level, requires learner engagement. Mathematics is not a spectator sport. Sometimes traditional teaching fails to actively involve students. One way to address the problem is through the use of interactive activities and this web site provides many of those. The Go Maths page is an alphabetical list of free activities designed for students in Secondary/High school.

Maths Map

Are you looking for something specific? An exercise to supplement the topic you are studying at school at the moment perhaps. Navigate using our Maths Map to find exercises, puzzles and Maths lesson starters grouped by topic.

Teachers

If you found this activity useful don't forget to record it in your scheme of work or learning management system. The short URL, ready to be copied and pasted, is as follows:

Alternatively, if you use Google Classroom, all you have to do is click on the green icon below in order to add this activity to one of your classes.

It may be worth remembering that if Transum.org should go offline for whatever reason, there is a mirror site at Transum.info that contains most of the resources that are available here on Transum.org.

When planning to use technology in your lesson always have a plan B!

Do you have any comments? It is always useful to receive feedback and helps make this free resource even more useful for those learning Mathematics anywhere in the world. Click here to enter your comments.

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Description of Levels

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Level 1 - Adding and subtracting numbers less than ten with one decimal place

Level 2 - Adding and subtracting numbers less than one hundred with two decimal places

Level 3 - Adding and subtracting decimal numbers with a different number of decimal places

Level 4 - Real life problems involving the addition and subtraction of decimal numbers

There is also an exercise on multiplication and division of decimals called Decimal Times.

Finally there's the Decimals topic page which includes lesson Starters, visual aids, investigations and self-marking exercises.

Answers to this exercise are available lower down this page when you are logged in to your Transum account. If you don’t yet have a Transum subscription one can be very quickly set up if you are a teacher, tutor or parent.

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Adding and Subtracting Decimals

This video will teach you how to perform the basic operations with decimals.

Don't wait until you have finished the exercise before you click on the 'Check' button. Click it often as you work through the questions to see if you are answering them correctly. You can double-click the 'Check' button to make it float at the bottom of your screen.

Answers to this exercise are available lower down this page when you are logged in to your Transum account. If you don’t yet have a Transum subscription one can be very quickly set up if you are a teacher, tutor or parent.

Log in Sign up

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