Calculators

Using a calculator can be very helpful in mathematics but it’s important to

know how to use the calculator correctly, or you could still end up with the

wrong answer.

Difficult, long-winded question may need more than one step if you want to

get the answer right.

Example 1.

Let’s say that the question we got is (49.2 + 7.6) – (18.75 x 2). We’ll break this

down into steps.

- First, we’ll do 49.2 + 7.6 and write its answer down.
- Then, we’ll do 18.75 x 2 and write its answer down
- Finally, we can do the subtraction.

Using a calculator to convert fractions to decimals is really easy! All you need

to do is divide the numerator by the denominator.

Example 2.

If we needed to convert into a decimal, all we need to do is take 5 and

divide it by 8.

5 ÷ 8 = 0. 875 therefore = 0.375

Calculators are also really handy when you’re trying to find the answer to a

question that might take a lot of working out.

Example 3.

Let’s say the question we’ve been given is ‘find two numbers that add together

to make 20 and multiply together to make 96’.

We know which pairs of numbers will add together to make 20 so let’s do a

couple of sums to try and guess the answer.

10 x 10 = 100 – this answer is too big

15 x 5 = 75 – this answer is too small

The real answer must be in between these two

12 x 8 = 96 – we got the right answer

With a calculator, we could have done lots of sums very quickly to get the right answer.

Related Topics

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