Division as repeated subtraction
Remember how MULTIPLICATION is repeated addition:
5 × 4 = 4 + 4 + 4 + 4 + 4 = 20.
You drew or added __ groups of four.

Let's reverse the process. You start out with 20 sticks.
20 − 4 − 4 − 4 − 4 − 4 = 0
This is repeated subtraction. You subtract 4 repeatedly, or many times, till you hit zero. Each subtraction is forming a group of 4. How many groups did you form? How many times did you subtract? That is the answer to the division problem 20 ÷ 4. 
Try it yourself: Separate groups, but in your mind 'move them away' or subtract.
42 ÷ 3                                            42 ÷ 14 
DIVISION is repeated subtraction:

Often, it is handier to actually add instead of subtract:

Example problems
1. Write a multiplication sentence AND a division sentence that fits the addition/subtraction facts.
5 + 5 + 5 = 15
15 − 5 − 5 − 5 = 0
__ ÷ __ = __
__ ÷ __ = __

12 + 12 + 12 + 12 = 48
48 − 12 − 12 − 12 − 12 = 0
__ ÷ __ = __
__ ÷ __ = __

23 + 23 + 23 = __
__ − 23 − 23 − 23 = 0
__ ÷ __ = __
__ ÷ __ = __

40 + 40 = __
__ − 40− 40 = 0
__ ÷ __ = __
__ ÷ __ = __

2. Write a subtraction sentence for each division sentence.
45 ÷ 15 = __
45 − 
32 ÷ 8 = __
32 − 
Mudah faham.
ReplyDeleteya, ini sesuai dengan murid tahun 2 atau 3.
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