Mastering Decimal Operations with Powers of Ten

Maria Miller from Math Mammoth explains how to multiply and divide decimals by powers of ten. The lesson covers shortcuts for multiplying whole numbers and decimals by ten, hundred, and thousand, emphasizing the movement of the decimal point. It also explains why this method works using a place value table. The video includes practice problems to reinforce the concepts.

What is the shortcut for multiplying whole numbers by 1000?

• Move the decimal point three places to the left

• Add three zeros to the number

• Subtract three zeros from the number

• Move the decimal point three places to the right

When multiplying a decimal by 100, how many places do you move the decimal point?

• Two places to the left

• One place to the left

• Two places to the right

• Three places to the left

If you multiply 0.006 by 1000, what is the result?

• 600

• 6

• 0.6

• 60

What happens to the number 3.2 when multiplied by 1000?

• It becomes 32

• It becomes 0.32

• It becomes 320

• It becomes 3200

Why does moving the decimal point to the right make the number larger?

• Because it removes digits from the number

• Because it adds more digits to the number

• Because it decreases the place value of each digit

• Because it increases the place value of each digit

What is the shortcut for dividing a number by 10?

• Move the decimal point one place to the left

• Move the decimal point one place to the right

• Subtract one zero from the number

• Add one zero to the number

If you divide 72.65 by 10, what is the result?

• 7.265

• 72.65

• 0.7265

• 7.265

When dividing a decimal by 100, how many places do you move the decimal point?

• Two places to the right

• Three places to the right

• Two places to the left

• One place to the right

What is the result of dividing 6.4 by 100?

• 6.4

• 0.64

• 64

• 0.064

Why does moving the decimal point to the left make the number smaller?

• Because it adds more digits to the number

• Because it increases the place value of each digit

• Because it decreases the place value of each digit

• Because it removes digits from the number