Page 18 - 新思维数学教师用书3 试读样张

MATHEMATICS 3 TEACHER’S RESOURCE

Convincing
Convincing involves presenting evidence to justify or challenge mathematical ideas or solutions.
Learners persuade people (e.g. a partner, group, class or an adult) that a conjecture is true.
Example 1:
Kiko spilt some ink on the ones digits in her calculation.

24 + 13 = 381

What could her calculation have been?
Did you find all the possibilities for Kiko’s calculation?

(Stage 3 Unit 3.1 Think like a mathematician)
Learners will show they are convincing (TWM.04) when they use their knowledge and understanding
of numbers to explain how they know that they have found all the possible solutions for
Kiko’s calculation.
Example 2:
Sofia says that if you are sorting multiples of 2, 5 or 10 in a Venn diagram, the multiples of 10 always
belong in the overlap and it does not matter which two sets of multiples you sort. Do you agree with
Sofia? How do you know?
(Stage 3 Exercise 5.1 Think like a mathematician 1)
Learners will show they are convincing (TWM.04) when they present evidence to justify whether or
not they agree with Sofia.

SENTENCE STARTERS
• I know that … because …

• You can see that …
• I agree with … because …

• I disagree with … because …
• I think that … because …

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4+ ྍනົඔ࿐࢝ഽႨ඀ ᆞ໓č1 Ď ཮@නૼ JOEE