What is the product of any number and zero?

• A. 0
• B. The number
• C. It depends on the other factor
• D. Undefined

Answer: (A)

Multiplication by zero always gives zero, because it asks how many objects you have when you have zero groups of something. If there are zero groups of items, you have nothing at all, so the product is zero. You can also see this with repeated addition: multiplying a number by zero means adding that number to itself zero times, which leaves zero. For example, 6 × 0 and 0 × 6 both equal zero. It’s not the number itself, and it isn’t undefined—the result is clearly zero, unchanged regardless of the other factor.