Multiplying Decimals by Powers of Ten

Multiplying Decimals and Powers of 10, Whole Numbers, and Decimals

​Powers of 10

• ​10, 100, 100, etc. are all powers of 10

• ​When we multiply a decimal number by a power of ten, we count the number of 0s in the power of 10 and move the decimal point that many places to the right.

• ​Powers of 10 can also be represented with an exponent. The exponent tells you the number of 0s that power of 10 has.

Multiple Choice

How many 0s does this power of ten have?

• 3

• 2

• 4

• 0

Multiple Choice

How many 0s does this power of ten have?

100

• 100

• 2

• 10

• 1

Multiple Choice

2.35 x 1,000 =

• 0.00235

• 23.5

• 235

• 2,350

Multiple Choice

$$10^2\cdot0.034\ =$$  

• 3.4

• 34

• 0.34

• 340

​Multiplying Decimals

• ​First, you multiply as if as though you were just multiplying whole numbers.

• ​Next, count the number of digits are right of the decimal point in each factor.

• ​Finally, move the decimal point in your product to the left that many times.

Fill in the Blank

$$23.4\left(9.1\right)\ =$$  

Fill in the Blank

$$0.99\ \cdot\ 1.1$$  

Fill in the Blank

$$11\times3.14$$  

Fill in the Blank

$$\left(2.7\right)\left(0.21\right)$$  

Fill in the Blank

$$17\times8.1$$