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Multiplying and Dividing with Place Value Materials
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| Place value materials are useful for developing multiplication and division skills only in a limited way - for multiplying by 1-digit numbers and for dividing by 1-digit numbers. For more complex situations the materials tend to confuse the matter rather than assist in developing it. |
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| Using PV materials for multiplying by 1-digit numbers
Consider 3 x 48. This can be viewed as adding 48 three times.
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| Step 1: Build 48 three times |
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| Step 2: Trade |
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| Step 3: Combine traded and remaining PV materials |
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PV Materials represent answer:
3 x 48 = 144
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| Traded PV materials |
Remaining PV materials |
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Using PV materials for dividing by 1-digit numbers
Consider 65 ÷ 5. This can be viewed as forming five equal groups.
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| Step 1: Build 65 |
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| It is not possible to form 5 equal groups of tens. Trading is needed (1 ten for 10 ones). |
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| Step 2: Trade 1 ten for 10 ones |
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The trading results in 5 tens and 15 ones.
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| Step 3: Form 5 equal groups. |
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The answer is represented by one of the equal groups.
65 ÷ 5 = 13
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| For more detail, refer to: |
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Grade 4 Multiplication Algorithm
Grade 4 Division Algorithm
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3 x 234 |
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Try these. |
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268  2 |
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