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Topic: How does Singapore Maths explain negative multipliers & divisors?
Replies: 0

 Jonathan J. Crabtree Posts: 355 From: Melbourne Australia Registered: 12/19/10
How does Singapore Maths explain negative multipliers & divisors?
Posted: Dec 12, 2016 8:39 PM

I bought the complete set of Singapore Maths books from Earlybird Preschool Maths 1A all the way toP rimary Maths 6B. Now I want to know the definition of a negative number. You usually find patterns.
5 - 2 = 3
4 - 2 = 2
3 - 2 = 1
2 - 2 = 0
1 - 2 = -1
0 - 2 = -2 and so on.

But where and how does Singapore Mats DEFINE a negative number? For example, Does it teach n - n = 0 or +n + -n = 0?

Also, how does Singapore Math explain say, negative three multiplied by negative two? Again, elsewhere you just see patterns such as
- -3 x +3 = -9
- -3 x +2 = -6
- -3 x +1 = -3
- -3 x 0 = 0
- -3 x -1 = +3
- -3 x -2 = +6 and so on.

Surely there has to be a more intuitive explanation than this forced logic!

Also, I would also really like to see the Singapore Maths explanation of division with a negative divisor.

Of course it's possible Singapore Maths just ignores the meaning of division with negative divisors like most other mathematics texts.

Hope you can help!

Jonathan