Everyday maths 2 (Wales)
Everyday maths 2 (Wales)

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

Free course

Everyday maths 2 (Wales)

3.1 Rounding to a degree of accuracy

Watch the short video below to see an example of how to round to 1, 2 and 3 decimal places.

Download this video clip.Video player: bltl_1_2_3_rounding.mp4
Skip transcript

Transcript

Rounding can be used when you're asked to give an answer to a given degree of accuracy. This is called rounding to decimal places, or d.p. In this video, you'll look at how to round to one, two, and three decimal places.

Take the number 25.782. How would you write this rounded to one decimal place? This is the first decimal place. Rounded to 1 d.p., the number could be either 25.7 or 25.8. Look at the digit next to the number 7. If this number is equal to or greater than 5, add one more. If it's less than 5, leave it. In this case, 8 is greater than 5, so our number rounded to 1 d.p. is 25.8.

Now, let's around a number to two decimal places. A common example of when you would do this in daily life is when dealing with money. If you were at a restaurant and needed to split a bill of £87.95 between three people, you would first calculate the division. £87.95 divided by 3 equals £29.3166667. Clearly, you cannot pay this exact amount. So how much would you pay if the amount per person was rounded to two decimal places?

This is the second decimal place. Look at the number next to it. Is it greater than or equal to 5? 6 is more than 5, so you need to add 1. The amount to pay is £29, 32 pence.

Let's try another example. How would you around the number 35.496 to two decimal places? This is the second decimal place. Look at the number next to it. 6 is greater than 5, so you need to add one more. In this case, the rounded number would be 35.50.

Can you round to three decimal places? Have a go with this number: 412.5762. The number next to the third decimal place is 2, which is less than 5. This means the correctly rounded number is 412.576.

End transcript
 
Interactive feature not available in single page view (see it in standard view).

Remember this rounding rhyme to help you:

Described image
Figure 5 A rounding rhyme

Activity 8: Rounding skills

Practise your rounding skills by completing the below.

  1. What is 24.638 rounded to one decimal place?

  2. What is 13.4752 rounded to two decimal places?

  3. What is 203.5832 rounded to two decimal places?

  4. What is 345.6794 rounded to three decimal places?

  5. What is 3.65 rounded to the nearest whole number?

  6. What is £199.755 to the nearest penny?

  7. What is £37.865 to the nearest pound?

  8. What is 61.607 kg to the nearest kg?

Answer

  1. 24.6

  2. 13.48

  3. 203.58

  4. 345.679

  5. 4

  6. £199.76

  7. £38

  8. 62 kg

FSM_2_CYMRU

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to University-level study, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371