Estimate 587 ÷ 2.9

Step by step

The question

Question: estimate 587 ÷ 2.9.

To estimate means to find about how big the answer is.

We make every number easy first.

1 Round to 1 significant figure

We round each number to 1 significant figure: only its first figure stays.

587: the first figure is 5.

The next digit is 8, 5 or more, so we round up: 600.

2.9: the first figure is 2.

The next digit is 9, 5 or more, so we round up: 3.

2 Work it out

So the answer is about 600 ÷ 3.

Now it is easy to work out.

Careful!

We changed the numbers.

So we write ≈, about, not =.

600 divided by 3 is 200.

So the answer is about 200.

3 Check

Let's check with a calculator.

The exact answer is about 202.4.

That is close to 200.

So the estimate is good!

Let's look back.

First: round to 1 significant figure.

Then: work it out.

Last: check.