# The Bad and the Ugly #2

**This one was spotted in a school's 'maths specialist room'.**

It seems from this information poster that '**=**' can mean "same as", "equals" or "**Total**"... two out of three aint bad. The "**Total**" part is clearly nonsense of course because we already have a perfectly good sign for that (**+**).

**=** means "equals", "Equivalant to", "is the same as" or "balances".

Luckily we managed to get the poster taken off the wall straight away.

If you've spotted anything that is erroneous and annoying feel free to moan about it in the comment box below. I'd love to hear your thoughts.

## Re the comment on using the

## I'm very hot on using

I'm very hot on using vocabulary accurately... without that we are in danger of confusing all the students and children we work with. I'll leave the last word on this to

Barry Mazurof Harvard - this is well worth a little study:When is one thing equal to some other thing?## The maths symbol = does not

## CecKitKat, While I clearly

CecKitKat,

While I clearly agree with you in some parts here, I think you are confusing common 'day-to-day' usages with mathematical ones. The technical (mathematical) definition of

equalityis the state of being"quantitatively the same... Being the same or identical to in value". Therefore, it is both reasonable and correct to say that 3+2 is "the same as" 5, if we are speaking in terms of value (which we are). Similarly, any good shopkeeper will tell you that 3p plus 2pis the same as5p! If we were to follow your argument to its logical conclusion we would have to say, when faced with two 5p coins, that the first 5p is not the same as the second 5p ... since the first is adifferentcoin (I'm sure there's a joke puzzle based on this type of misconception). This, however, is the common 'day-to-day' meaning of same as, not our mathematical one. Likewise, confusion could be had with the use of 'similar' in geometry, where again the term does not match 'day-to-day' usage. Vocabulary is extremely important, and we must get it right to help our young learners fully understand the logic and beauty of mathematics.My initial argument with the poster maker was that '='

cannot ever mean'Total' - with that, at least, I am sure we both agree.On a positive note, I returned to the school a few weeks later and found that the poster had been removed. So all's well that ends well.

John

## Yes perhaps you need to look

## Carol, thanks for the link.

## Hmmmmm I think you need to

## This will be great in