Using Memory On Your Calculator

Clear explanations and worked examples from the Math-Mate school maths textbook.

When you have complicated questions that involve a few steps it can be quite useful to know how to use the memory in your calculator to store values. If, as you work through a question, you calculate some intermediate values that you want to remember for later, rather than writing down all the digits on paper, you can use your calculator’s memory to store the value. Here’s an example question:

Now, if you carry out the operations in the correct order, then you’ll have to do this question in 3 steps. First you’ll have to evaluate the expression inside the first set of brackets. Secondly you’ll have to evaluate the expression inside the second set of brackets. And last of all you’ll have to multiply those two numbers together. It would be nice to be able to store the value you get when you evaluate the first set of brackets. This would mean you wouldn’t have to write it down on paper to remember it. Here is how you can do that with our two calculators:

Calculator memory instructions

Mathematical diagram

Calculate – you should get .

To store this value, press the button. This tells the calculator that we want to store the value.

Next, we need to tell the calculator where to store the value. There are six easy places we can store the value – A, B, C, D, E and F. In the diagram they are called storage variables. Let’s store this value at A, by pressing the button.

Next calculate what is using your calculator. You should get 9.984. So we’ve now worked out what the first bit and the second bit of the expression equal. Now all we have to do is multiply them together.

You should have the 9.984 on your display. To multiply this by the value we calculated for , press the ‘×’ button. Your calculator will display something like ‘Ans ×’, Ans means the last answer that you got, which was 9.984. Now we want to multiply this value by what we worked out for , which is stored in A.

Press the button, then press the button. By pressing the button, we tell the calculator that we want to use the ‘A’ variable, instead of the function. Your display should now say something like: ‘Ans×A’. Press the ‘=’ button and you’ll get your answer – it should be something like 14.8662 (I’ve rounded to 4 decimal places).

Calculate – you should get 1.489

To store this value, press the button. This stores the value in the calculator’s memory.

You should have 9.984 on your display. We want to multiply this by the value we worked out for . This is stored in the calculator’s memory. First press the ‘×’ button.

Now press the button to bring back what we stored in the calculator’s memory. The display will now show the value stored in memory: 1.489.

Now press the ‘=’ button.

You should get 14.8662 on your display (I’ve rounded to four decimal places).