## Presentation on theme: "Multiplication Made Easy"— Presentation transcript:

What is multiplication?
Rows and columns 4 x 3= 4 groups of 3

1-same as the number; imagine it as one group of the number
2 3 4 5 6 7 8 9 10

2-double the original 1 2 3 4 5 6 7 8 9 10 12 14 16 18 20

4- we double the number than double again!
1 2 3 4 5 6 7 8 9 10 12 14 16 18 20 24 28 32 36 40

4s If 4 x 6= 6x2x2=12+12=24 Then 234x4=234x234=(468)x2 =936
Try 22x4=______

3- we double the number and then add one more set
1 2 3 4 5 6 7 8 9 10 12 14 16 18 20 15 21 24 27 30

Square numbers-make a diagonal on the number chart
1 2 3 4 5 6 7 8 9 10 12 14 16 18 20 15 21 24 27 30 28 32 36 40 25 49 64 81 100

Also 11x11=121 12x12=144 Try 13x13=____

10-just add a zero 1 2 3 4 5 6 7 8 9 10 12 14 16 18 20 15 21 24 27 30 28 32 36 40 25 50 60 49 70 64 80 81 90 100

10s 10x5=50 (5 and add a zero at the end) 10x 234=2340
Try 10 x 3456=_______ Try 1000 x 239=_______

5-multiply by 10 and then divide by two; all numbers end with 0 or 5
2 3 4 5 6 7 8 9 10 12 14 16 18 20 15 21 24 27 30 28 32 36 40 25 35 45 50 60 49 70 64 80 81 90 100

5s Try 5 x4= (10 x 4)/2=40/2=20 Try 5 x32= Try 5 x 400=

9-multiply by 10 and remove a set; the digits always add to 9
2 3 4 5 6 7 8 9 10 12 14 16 18 20 15 21 24 27 30 28 32 36 40 25 35 45 50 54 60 49 63 70 64 72 80 81 90 100

9s If 9x4=36 (10x4-4) Then 9x43= ____ (10x43-43) Try 9x290=________

6x7; 6x8; 7x8= the ugly ones 1 2 3 4 5 6 7 8 9 10 12 14 16 18 20 15 21 24 27 30 28 32 36 40 25 35 45 50 42 48 54 60 49 56 63 70 64 72 80 81 90 100

The ugly ones 6x7=42 (e.g. 6x7=(6x6)+(6x1)) 6x8=48 7x8=56

11—double the digit 1 2 3 4 5 6 7 8 9 10 11 12 14 16 18 20 22 15 21 24 27 30 33 28 32 36 40 44 25 35 45 50 55 42 48 54 60 66 49 56 63 70 77 64 72 80 88 81 90 99 100 110 121

12 1 2 3 4 5 6 7 8 9 10 11 12 14 16 18 20 22 24 15 21 27 30 33 36 28 32 40 44 48 25 35 45 50 55 60 42 54 66 72 49 56 63 70 77 84 64 80 88 96 81 90 99 108 100 110 120 121 132 144

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