Multiplying When the Basic Fact Ends in Zero
Multiplying When the Basic Fact Ends in Zero (Chapter 4 instance) is a Grade 4 math skill in enVision Mathematics, Chapter 4: Use Strategies and Properties to Multiply by 2-Digit Numbers. Students annex all zeros from original factors to the basic fact product, paying special care when that product itself ends in zero.
Key Concepts
When multiplying multiples of 10, first find the product of the basic fact. Then, annex (attach) all the zeros from the original factors to the end of that product, even if the product of the basic fact already ends in a zero.
Common Questions
What is the rule for multiplying when the basic fact ends in zero?
Find the basic fact product first, then annex all zeros from the original factors to it. Even if the basic fact already ends in zero, you must still add the zeros from the factors.
What is the difference between a zero in the basic fact and zeros from factors?
The zero in the basic fact product is part of the answer value, not a place holder from the factors. You still need to add the factor zeros separately after the basic fact result.
What is an example from Chapter 4?
For 50 times 60: basic fact is 5 times 6 equals 30. Annex 2 more zeros (from 50 and 60) to get 3,000. The zero in 30 is not one of the annexed zeros.
How do you avoid mistakes when multiplying multiples of 10?
Clearly identify which zeros come from the original factors and which zeros are part of the basic fact result. Only the factor zeros get annexed at the end.
What chapter in enVision Grade 4 covers this multiplication skill?
This multiplication skill is covered in Chapter 4: Use Strategies and Properties to Multiply by 2-Digit Numbers in enVision Mathematics Grade 4.