Q 1: The best way to check multiplication is by repeated addition.|
Q 2: To check multiplication by estimation, round each factor to its greatest place value and then multiply. First round each factor DOWN and multiply. Then round each factor UP and multiply. The original product should fall between the two estimated products.|
Q 3: Check multiplication for 255x49=12,495. Round both factors down and multiply that is 200x40=8000. Round both factors up and multiply that is 300x50=15,000. 8000 < 12,495 < 15,000|
The original number is equal to one of the estimated products.
The original number does not falls between estimated products.
The original number falls between estimated products.
Q 4: There are different ways to check multiplication. Choose the correct answer.|
changing the order of factors and multiplying again
Repeated addition which can be tedious large numbers
all the other answers
Estimation lets you know if your answer is "about right"