Round 715 to 2 significant figures Step by Step

Step by step

The question

Question: round 715 to 2 significant figures.

Round 715 to 2 significant figures

1 Find the first significant figure

The first significant figure is the first digit that is not 0.

In 715, it is 7.

= 715

significant figures: counted from

the first digit that is not 0

2 Count the figures

We count 2 figures from there: 7, 1.

The 2nd figure, 1, is in the tens place.

So we round to the nearest ten.

= 2nd figure 1 → the tens place

3 Look at the next digit

Now we look at the next digit to the right.

It is 5.

5 or more: we round up.

4 or less: we round down.

5 is 5 or more, so we round up.

= 5 is 5 or more → round up

5 or more → up: digit + 1

4 or less → down: digit stays

4 See it on a number line

715 is exactly halfway.

Halfway rounds up, to 720.

5 Keep the size

The places after the 2nd figure become 0.

The zeros keep the size: 720 is close to 715.

= 715 ≈ 720

Careful!

72 is much smaller than 715.

The zeros keep the number the right size.

Careful: not 715 ≈ 72 ✗

So 715 to 2 significant figures is 720.

6 Check

Let's check.

720 has 2 significant figures: 7, 2.

720: figures 7, 2 → 2 s.f.

And it is the same size as 715: 3 digits before the point.

So the answer is right!

715 and 720: both 3 digits before the point

Let's look back.

First: find the first significant figure.

Then: count the figures.

Then: look at the next digit.

Then: see it on a number line.

Then: keep the size.

Last: check.

Answer