When both numbers you multiply end with zeros, you can use place value to make the problem easier. First, multiply the nonzero digits. Then, count all the zeros in both numbers and add them to the end of your product.
This method works because each zero represents a power of ten. Multiplying by tens, hundreds, or thousands increases the value by those powers of ten.
Follow these steps to multiply large numbers that both end in zeros accurately and quickly.
Be careful not to lose or add extra zeros. Double-check by estimating — your answer should make sense in size.
Here are several examples showing how to multiply whole numbers that both end with zeros.
Counting zeros correctly is key. The more zeros in your factors, the greater the product will be.
Zeros at the end of whole numbers show that the number has been multiplied by ten, one or more times. When you multiply two such numbers, you are combining their powers of ten.
This shows that each zero represents a power of ten, and multiplying powers of ten adds their exponents. That’s why we count and add the zeros in our shortcut method.
After solving, you can estimate or use smaller numbers to make sure your answer makes sense.
Estimation helps catch mistakes with zeros or misplaced digits. Always review your final product carefully.