Show:
box method
partial products
facts
factors and multiples
10

23x4

(20+3) x 4

20x4=80

3x4=12

92

10

29x5=

(20+9)x5

20x5=100

9x5=45

145

10

5x500

2,500

10

all factor pairs of 12

1x12

2x6

3x4

20
156x3=
(100+50+6)x 3

100x3=300

50x3=150

6x3=18

468

20

154x2=

(100+50+4) x 2

100x2=200

50x2= 100

4x2= 8

308

20

40x60

2,400

20

the first 5 multiples of 3

3, 6, 9, 12, 15

30

36x12=

(30+6)x(10+2)

30x10=300

30x2=60

6x10=60

6x2=12

432

30

12x18

(10+2) x (10+8)

10x10=100

10x8=80

2x10=20

2x8 = 16

216

30

400x300

120,000

30
all factor pairs of 20

1x20

2x10

4x5

40
78x31

(70+8)x(30+1)

70x30=2100

70x1=70

8x30=240

8x1=8

2,418

40

62x26

(60+2)x(20+6)

60x20=1,200

60x6=360

2x20=40

2x6=12

1,612

40
900x600

540,000

40
first 5 multiples of 8

8, 16, 24, 32, 40

50
121x43
(100+20+1)x(40+3)

100x40=4000

100x3=300

20x40=800

20x3=60

1x40=40

1x3=3

5,203

50

234x56

(200+30+4)x(50+6)

200x50=10,000

200x6=1,200

30x50=1,500

30x6=180

4x50=200

4x6=24

13,104

50

300xn=18,000

n=60

50

all factor pairs of 48

1x48

2x24

3x16

4x12

6x8