The Murky World of BODMAS!

August 3, 2014 § Leave a comment

Recently a parent asked me about a question they had come across in one of their 11 Plus practice papers. Their child had put E as the answer and his Mum was sure this was correct, but the answer book said it should have been A.

The answer came down to BODMAS (or BIDMAS). It’s one of those awkward little things that no one ever remembers! But, it’s something that rears its head in 11 Plus, SATs and GCSE exams.
BODMAS is basically the order in which we complete a complex sum. It stands for:

Brackets
Orders (or Indices)
Division
Multiplication
Addition
Subtraction

It reminds us that when dealing with a sum, we have to do whatever is in the brackets first, then deal with any indices (e.g. square numbers or cube numbers), then we can do divisions and multiplications, then finally additions and subtractions.

We must be careful, though, because all is not as it seems when it comes to BODMAS!

Although Addition comes before Subtraction, this does not mean that all the additions have to be done before the subtractions. For instance, 6 – 3 + 1 is done from left to right, so the answer is 4. If you were to do the adding first, you would get an answer of 2, but this is not correct. So, really, BODMAS should be read as:

Brackets first
Orders or Indices next
Then any Divisions and Multiplications in order from left to right
Then any Additions and Subtractions in order from left to right

Basically, BODMAS sounds better than BOMDSA! It’s just a reminder to do your multiplications and divisions before moving on to your additions and subtractions.

So, that brings us to the question the parent raised. The question was:

Which of the following gives the same answer as 6 x 2 + 12?
A. 48 – 8 x 3     B. 3 + 11 x 2     C. 3 x 7     D. 24 ÷ 2 – 1     E. 2 + 4 x 4

Using the rules of BODMAS, 6 x 2 + 12 = 12 + 12 = 24
A. 48 – 8 x 3 = 48 – 24 = 24
B. 3 + 11 x 2 = 3 + 22 = 25
C. 3 x 7 = 21
D. 24 ÷ 2 – 1 = 12 – 1 = 11
E. 2 + 4 x 4 = 2 + 16 = 18

And that is why the answer is A, not E!

Maths Star’s brand new Level 5 Mathematics Pack is now available to download!

July 10, 2011 § Leave a comment

The level 5 maths pack covers 36 all-important topics aimed at students in Years 5 and 6 at school. The 36 topics have been chosen to relate to the 11 Plus maths topics, so they are a perfect revision aid for the exams. They also build important SATs skills and help to revise all the different areas of maths that are likely to appear in Year 6 SATs tests.

Each topic has a full and detailed explanation with exam reminders, followed by a series of practice questions. At the end of the pack are 7 revision sheets that students can use during their final week before the exam to brush up on their skills.

You can choose to have the pack emailed to you or you can pay extra to have it printed and posted to you. Emailed versions will be attached to your confirmation email. Posted versions will be with you within 5 working days. If you have any questions or have problems with your order, please contact us at mathsstaruk@gmail.com

Click here of list the topics covered in this pack

Our new Level 5 Maths Pack is designed to help your child with 11 Plus topics
The pack contains worksheets & answers covering 36 topics and 4 revision sheets

11 Plus Essex Tests

November 15, 2010 § Leave a comment

The Essex tests are fast approaching and students and parents are getting nervous! Like all grammar schools, the grammars in Essex are very sought-after and many parents would love for their child to go to school like King Edward Grammar (KEGS) and Colchester Grammar. This means it is important for children to be as well-prepared as possible for the tests in order to stand up to the large amount of “test-takers”.

The Essex tests are made up of the following elements:
 – Standard Format Mathematics
 – Multiple Choice Verbal Reasoning
 – Comprehension-style English

It is very difficult to find Essex 11 plus practice papers, especially for the distinctive English tests. Why not try our practice papers page. And don’t forget our eleven plus maths site: www.elevenplusmaths.co.uk where you can find helpful maths revision worksheets.

And, of course, we wish everyone taking the Essex entrance exams the best of luck! Do your best and make sure you CHECK THOROUGHLY!!

How To Do Percentages

November 1, 2010 § 2 Comments

Percentages are another tricky subject that often confuses children at school! Just like fractions, there is so much to learn about working with percentages: finding the percentage of a quantity, changing decimals and fractions into percentages and vice versa, not to mention finding one quantity as a percentage of another! Percentages, though, are a vital tool for later life. Many of us use percentages in our day-to-day life without even thinking about it, simply by working out VAT!

So, what is a percentage? A percentage is a way of expressing a number as a portion of 100.

How do we use percentages? We say that 100 is the whole of something and the percentage is the amount of it we are using. (For example, we say that a whole cake is 100%. If I eat half of that cake, we are left with 50%.)

Very often, it is much easier to use fractions, but when it comes to really complicated fractions, it is sometimes just easier to say 79% instead of 79 hundredths! Again, percentages is one of those topics that a child can often fall behind in because they have not understood a certain part of it. That’s why it’s always best to start at the beginning if your child is ever going to be confident about using percentages in the 11+ exams or at any stage in their school life. Don’t forget that percentages will take up a few questions in GCSE mathematics!

Do I know what a percentage is?

Can I change a fraction into a percentage?

Can I change a decimal into a percentage?

Can I find the percentage of a quantity?

Do I know the simpler methods for using percentages like 25% and 50%?

If your child can answer “yes” to all those questions, they are a percentages maths star! If there are a few “no”s, try Maths Star’s 11+ Percentages page.

11 Plus Mathematics Practice Paper

October 27, 2010 § 1 Comment

Practicing papers is one of the most effective ways of preparing for the 11 plus exams. There are lots of suggestions out there about how best to use practice papers as a revision tool, but at the end of the day it comes down to each individual. Everyone has a different way of learning, so it’s best to judge according to your own child. Some children will be able to complete whole papers in one go, whereas for other children it is easier to do the papers in sections.

Whatever way of learning you choose, though, it is essential to make sure your child is comfortable working within the time constraints. Remember that many of the 11+ maths exams allow 1 minute per question, so this is what you are aiming towards. In some 11+ verbal reasoning and 11+ non verbal reasoning tests, only 45 seconds per question is allocated – no small task for a 10-11 year old! That’s why it is a good idea to make sure your child is prepared. You do not want the 11 plus exam to be a stressful ordeal.

There are many practice papers that you can buy from various bookshops, but why not try our free downloadable 11+ maths practice paper. It is 30 questions long and can be used either as a standard or a multiple choice format paper.

11+ Maths Practice Paper

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