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Great! I can use a calculator!
By David Hanson
08 May
David Hanson has over 40 years' experience of teaching, has been a member of the ISEB Mathematics exam setting team, and has written numerous titles for Galore Park, including the Mathematics for Common Entrance 13+ revision series. Here, he shares his seven Rs, which he believes are crucial to take on board when preparing for an exam such as the Mathematics for Common Entrance at 13+ calculator paper. 

For many candidates, being allowed to use a calculator will come as a big relief – but is this really good news? I can use a calculator, I am allowed to use a calculator and I know how to use a calculator are not the same!
 
Almost everyone will agree that, in all stages of education, the importance of the three Rs cannot be overemphasised. I have made a case in print elsewhere for the recognition that in education, and in later life, equal importance should be given to another seven Rs. In this short rambling about preparation for the 13+ calculator papers, I’ll attempt to indicate how six of these seven Rs can play an important part.
 
First, let us look briefly at the calculator itself. There is a bewildering array to choose from, with models to suit all budgets, and new, more sophisticated versions appear at frequent intervals. A wise parent will ensure that the candidate has the model recommended by the school. The most sophisticated or expensive calculator is unlikely to be the best for the purpose. To be absolutely safe, an identical, back-up calculator should not cost more than about £10, and this could prove to be a prudent investment.
 
It would be unwise to buy – or borrow – a new calculator just before an examination, just as it would be unwise to buy – or borrow – a new pair of trainers just before running a marathon! It is essential that a candidate is fully familiar with the calculator to be used in the examination, and this is where the first of the seven Rs comes into play. The calculator should be treated with RESPECT, as one would a helpful friend. The calculator can calculate results with incredible speed and accuracy, and can perform tasks that are beyond the capability of the human brain. The calculator should be given the same respect and care as a concert violinist would give to his or her instrument.
 
Unfortunately, as well as its strengths, a calculator has significant limitations! First, it doesn’t think! It will perform – perfectly – the task it is asked to do, but it must be given clear, correct instructions. There is no equivalent of a spellcheck to question an entry.
 
It will come as no surprise when I point out that the human also has limitations! We all know how easy it is to press the wrong key on a computer or mobile phone. Technology will often come to the rescue here, but with the calculator there is no help – except, perhaps, in a screen message such as ‘Syntax error’ which is not very helpful. Here we come to RELIABILITY. As with other typing errors, speed or lack of concentration is often the cause, so it is vital that a candidate makes calculator entries with great care, and it would be sensible to perform checks so that an incorrect entry does not waste valuable time at a later stage, or lead to loss of marks. Some errors result from not pressing a key (such as = at the end) rather than pressing the wrong key. If there is time, it is a good idea to repeat a calculation.
 
While parents and the school can play an important part in the preparation for the examinations, almost the whole burden of RESPONSIBILITY for calculator success rests upon the shoulders of the candidate. The candidate is responsible for being fully familiar with the calculator to be used in the examination, and for doing more than sufficient practice in the essential processes.
 
This brings us to RESOURCEFULNESS. A candidate should be able to recognise when it might be best not to use a calculator. Remember, it is the human that does the thinking and decides what to do. It is the human that checks if an answer is sensible and then communicates with the marker. The candidate chooses what task the calculator should perform, and decides how best to give it the necessary instructions. It is sensible to estimate the result expected from the calculator before performing the calculation, and to do a simple common-sense check afterwards. It is very important for the candidate to explain what is being done so that the marker could, if appropriate, award ‘method’ marks should an answer be incorrect. It is a good idea to write down all of the figures in the final calculator display before rounding to the required number of significant figures or decimal places.
 
It must be remembered that the calculator simply does the calculation. It does not know what the question is. If the question asks “How many 16-seater minibuses are needed to transport 100 pupils?”, the calculator result of 6.25 means that 7 minibuses are needed. However, if the question asks “How many pencils costing 16 pence could be bought for £1?”, the calculator result of 6.25 means that 6 pencils could be bought.
 
RESOLVE is required in order to master the techniques involved and to overcome difficulties encountered along the way. Using a calculator effectively is not as easy as some think, but practice makes perfect – or very nearly so.
 
RESTRAINT plays an absolutely vital part in success with a calculator. There may be a temptation to reach for the calculator immediately – and this could be a big mistake. There will be questions where a calculator is of no use whatsoever, and there may be some questions, such as finding the next number in a sequence, where it is the thinking, rather than the calculating, that is significant. On tackling a new question, my advice would be:

  • think what you need to do
  • decide if the calculator will help
  • estimate the likely result
  • write down what you are going to do
  • reach for the calculator.
Well, that is six of my seven Rs referred to at the start. I will just mention my seventh R, although it is hoped that this last R will play no part. If preparation is thorough, and care is taken in the examination, there should be no need for REGRETS (or REMORSE).
 
Great! I can use a calculator! I am allowed to use a calculator and I know how to use a calculator! Good luck!



David Hanson is the author of our popular revision series for 13+ Common Entrance and Common Academic Scholarship (CASE) 

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View David's titles

Tags: Common Entrance, David Hanson, Exam tips, Maths 13+

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