Multiply with Expanded Form

Multiply with Expanded Form

(it is basically the same thing as using the distributive property)

So far we have learned how to....

• Use the distributive property to break apart factors

• 4 x 12 as (4x10) + (4x2)

• Using the expanded form is pretty much the same thing. We just use it with even bigger numbers

Multiple Choice

What is expanded form for the number 17?

• 10 + 7

• 1 + 7

Multiple Choice

What is 147 in expanded form?

• 1+4+7

• 100+40+7

Now we can use expanded form to multiply bigger numbers!!!

4 x 212

• 212= 200 + 10 + 2

• (4x200) + (4x10) + (4x2)

• (800) + (40) + (8)

• 848

Multiple Choice

Which shows how you can break up 2 x 43?

• (2x4) + (2x3)

• (20) +(6)

Multiple Choice

What is the product of 2 x 43?

• 24

• 86

• 64

Using the expanded form to multiply

• Think of the number in expanded form

• Multiply the other factor with the value of the first digit

• Continue multiplying

• Add them all up

6 x 351

• 351 = 300 + 50 + 1 (expanded from)

• (6 x300) + (6x50) +(6x1)

• (1800)+(300)+(6)

• 1800+300= 2100 (think 18 +3 = 21)

• 2100+6= 2106

• 2106

3 x 363

• 363= 300 +60 +3

• (3 x 300) + (3 x 60) + (3 x 3)

• (900) + (180) + (9)

• 900 + 180 = 1,080

• 1,080+ 9 = 1,089

• 1,089

Multiple Choice

5 x 234

• 1170

• 1002