Mastering Multiplication of Decimals by Powers of Ten

In this video, Mr. J teaches fifth-grade students how to multiply decimals by powers of 10. The lesson begins with a review of multiplying whole numbers by powers of 10, then transitions to decimals. Mr. J explains that multiplying decimals involves moving the decimal point to the right, based on the number of zeros in the power of 10 or the exponent. He provides several examples and practice problems to reinforce the concept. The video concludes with a link to a mastery check for students to test their understanding.

What is the result of multiplying 9 by 10?

• 0.9

• 900

• 9.0

• 90

Why doesn't adding zeros at the end of a decimal number work when multiplying by 10?

• It changes the number's value

• It doesn't change the number's value

• It makes the number smaller

• It turns the number into a whole number

What happens when you move the decimal point to the right in a decimal number?

• The number becomes smaller

• The number becomes larger

• The number becomes a fraction

• The number remains unchanged

If you have 5 tenths and multiply it by 10 to the second power, what is the result?

• 0.5

• 5

• 50

• 500

What is the correct way to multiply a whole number by 100?

• Add two zeros at the end

• Both A and B are correct

• Move the decimal two places to the right

• Move the decimal two places to the left

What is the result of multiplying 22 and fifty-seven hundredths by a thousand?

• 225.7

• 22570

• 22.57

• 225700

When multiplying by 10 to the third power, how many places should the decimal be moved?

• 4 places

• 1 place

• 2 places

• 3 places

What is the result of 1.4 times 10 to the second power?

• 14

• 140

• 1.4

• 0.14

How does moving the decimal to the left affect the number's value?

• Increases its value

• Decreases its value

• Turns it into a whole number

• Does not change its value

What is the final step after moving the decimal to get the correct answer in standard form?

• Rewrite the number without the movement line

• Circle the final answer

• Remove any leading zeros

• Add zeros to the left