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Everyday maths 1

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# 2 Rounding

If you are out on a shopping trip, being able to quickly estimate the total cost of your shopping could help you to decide whether you have enough money to pay for it. Approximating answers to calculations is a very useful skill to have.

Figure 4 ‘Four or less, let it rest. Five or more, raise the score!’

Watch this video to refresh your knowledge on rounding. You should make notes throughout:

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Now try the following activities. Remember to check your answers once you have completed the questions.

## Activity 5: Rounding to 10, 100 and 1,000

1. Round these numbers to the nearest 10:
• a.64
• b.69
• c.65

Check with our suggestions before continuing.

Figure 5 A number line

You can see that:

• a.64 rounded to the nearest 10 is 60.
• b.69 rounded to the nearest 10 is 70.
• c.65 rounded to the nearest 10 is 70. (Remember: when a number is exactly halfway, you always round up. As the rhyme goes, ‘Five or more, raise the score!’)

Now practise rounding to the nearest 100. The rule is exactly the same.

1. Round these numbers to the nearest 100:
• a.325
• b.350
• c.365

Check with our suggestions before continuing.

Figure 6 A number line

You can see that:

• a.325 rounded to the nearest 100 is 300.
• b.350 rounded to the nearest 100 is 400.
• c.365 rounded to the nearest 100 is 400.

Now practise rounding to the nearest 1,000.

1. Round these numbers to the nearest 1,000:
• a.4,250
• b.4,650
• c.4,500
• d.4,060

Figure 7 A number line

You can see that:

• a.4,250 rounded to the nearest 1,000 is 4,000.
• b.4,650 rounded to the nearest 1,000 is 5,000.
• c.4,500 rounded to the nearest 1,000 is 5,000.
• d.4,060 rounded to the nearest 1,000 is 4,000.

Hint: In this activity you should round to the nearest pound, so £4.67 would be rounded to £5.

## Activity 6: Bill’s shopping

1. Bill has £20 to spend on his shopping. Here’s a list of the items he selects, along with how much they cost:

Figure 8 A shopping list

Use your rounding skills to work out whether Bill has enough money to pay for all of his shopping.