How to convert between standard units - ��˿�� Bitesize

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A one-minute video showing you how to convert between standard units using bar models.

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WHAT YOU NEED: Ruler, pen, calculator, tape measure and whiteboard.
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STEP 1: Write out the problem and circle the key information. Here you want to convert 140 centimetres into metres...
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…then draw two parallel bars and label the top one with the length that you know in cm, and the bottom bar with a question mark.
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STEP 2 - 100 cm = 1 m: Write on the conversion rate: 100 cm = 1 metre. On the top bar, estimate by eye where you think 100 cm would be, mark it with a vertical line and colour it in.
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STEP 3: Draw a line directly below on the bottom bar and colour that part in too. 100 cm = 1 m so this represents 1 m. Can you estimate, by eye, what the whole length of the bottom bar is in metres?
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You know that a metre is 100 cm. So to find out how many metres are in 140 cm, you divide by 100 cm. Write your calculation: the length you want to convert, 140 cm, divided by 100 cm. Before calculating it, can you estimate what the answer will be?
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STEP 4 - AMOUNT IN METRES: Use a calculator to check your estimate. Then write the answer where the question mark was on the bottom bar. Don’t forget the right units – you can write metres or the shorter ‘m’. You've done it!
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When you’ve worked out the answer, think about what it means in context. Can you visualise it?