Multiplying a Number by ZeroDate: 09/14/2001 at 10:24:41 From: Almas Subject: When zero multiply with number When any number is multiplied by zero, why is the result zero? Date: 09/14/2001 at 15:04:06 From: Doctor Ian Subject: Re: When zero multiply with number Hi Almas, Try thinking of multiplication this way. When we multiply two numbers - call them A and B - we'll take a yardstick of length A, and use it to move B steps away from zero. So 2 * 3 would look like this: 2 2 2 |---|---|---| <-- 2 * 3 +------------------------- 0 Note that multiplication is commutative - that is, you can multiply two numbers in either order: 2 2 3 |---|---|---| <- 2 * 3 +------------------------- 0 |-----|-----| <- 3 * 2 3 3 If I multiply something by 1, I just take the one step: 6 |-----------| <- 6 * 1 +------------------------- 0 Now, what happens if I multiply something by zero? I start at zero, and jump... no times at all! So I stay at zero, regardless of what the other number is. Does this make sense? - Doctor Ian, The Math Forum http://mathforum.org/dr.math/ |
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