Starter%20Activity

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LQ Are some subtraction methods better than others? RAG
Key Words Calculation, Operation, Accuracy, 7-Aug-19
Starter Activity Think / Pair / Share If you
know that 321 68 389, what else do you
know?
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392 124 (4 x 100) (11 x 10) (6 x 1)
Write a comment or ask a question.
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392 124 (4 x 100) (11 x 10) (6 x 1)
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3.92 12.4 ( ) ( ) (
)
Would it work for decimal numbers?
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392 - 124 ( ) ( ) ( )
Would it work for subtraction?
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Choose a question that you can answer
confidently. Write your answer on your mini
whiteboard. You must show how you worked it out.
83 - 34 539 - 426 323.5 - 172.9 122.4 - 34.71
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Class Methods 83 - 34
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Class Methods 539 - 426
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Class Methods 323.5 - 172.9
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Class Methods 122.4 - 34.71
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Longhill School Raise Money for the RNLI
The RNLI have over 4500 volunteer members.
Every volunteer needs to be trained in search
and rescue techniques and life saving
skills. Volunteers have to go on training
courses and they need to have specialist
equipment and clothing. In this lesson you will
be using subtraction techniques to calculate the
amount of money left after some of some of these
items have been purchased.
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Peer Assessment

• Swap your book with someone else on your table.
• Ask your partner to explain their working out to
  you.
• Is it clear how they have worked out their
  answer?
• Check their answer with a calculator. If they
  have made a mistake can you work out where they
  went wrong?

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Are some subtraction methods better than
others? You must give reasons for your answer.
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Plenary - Progress Pyramid
One question I would like answered
Two things I am not sure about yet.
Three things I have mastered