Maths Question

[karting]

Hi,

Just a quick question....

Five times zero is zero. Right?

Why is this?

Why dosn't five times zero equal five?

Because if you think of it as you should always work from the left to the right hand side of a maths question you therefore start with a whole number which is five, then times that by zero, (which isn't a number) why are you still not left with that single whole number, five? Why does a whole number suddenly disappear into thin air?

I know i am wrong according to the 'maths books, teachers and everyone else in the world' but why is this so?

If someone could explain fully why this is, AND where that whole number disappears to, i would appreciate it.

Thanks Sam

[zaza]

Welcome to the Forums



The short answer is: by definition.

Another way to look at it is that 5 x 1 = 5. So you can't pick another number 'a' such that 5 x a = 5, because multiplication is a one-to-one mapping. Further, it doesn't matter how you divide 0 because you must still have 0. That is the concept of having nothing. The logical conclusion is that 0/5 = 0, and the result follows.



By the way, 0 is a number. It is on the number line; usually it is the origin.



zaza

[TBeck]

miltiplication is just repeated addition, in 5 x 0 you are adding 5 together zero times or in other words adding zero fives together. the other way around 0 x 5 is adding zero together 5 times, so 0+0+0+.....+0 = 0 for any number of zeros

[Issvar]

You have no apples, you invite 4 friends, who also each have no apples. How many apples do you have together? 5 People x 0 apples = 0 apples