05 – Estimating

We can use significant figures to get an approximate answer to a problem. Look at these examples.


Look at the first example and round all the numbers to 1 sf to make ‘easier’ numbers.


It changes to:

\frac{200 \times 40}{0.5}


Now the division is simpler and is:



which is 16,000

Your turn:


Round the 2nd example to 1sf and then calculate an estimate:

Enter your answer here:

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