Multiplying by 2-digit factors

Partial Products

How can we multiply 23 × 15

1. Draw a box and divide it into four pieces.

2. Write the value of each digit in the number 23 across the top. Then write the value of each digit in the number 15 on the side of the box.

20 310

5

How can we multiply 23 × 15

3. Multiply the two numbers that meet in each box.

20 310

5

200 30

100 15

How can we multiply 23 × 15

4. Add of the 4 products that are in the boxes together.

20 310

5

200 30

100 15

200 100 30+ 15

345

How can we multiply 23 × 15

23 × 15 = 345

20 310

5

200 30

100 15

200 100 30+ 15

345

Multiply 47 × 24

1. Draw your box

2. Label the box

40 720

4

3. Multiply

800 140

160 28

4. Add

800 160 140+ 281128

Multiply 73 × 46

1. Draw your box

2. Label the box

70 340

6

3. Multiply

2800 120

420 18

4. Add

2800 420 120+ 183358

Multiply 37 × 18

30 710

8

300 70

240 56

300 240 70+ 56

666

Try the following problems on your own in your math journal.

1. 63 × 542. 95 × 373. 46 × 834. 27 × 62