Help.  My wife is taking pre-algebra and having a terrible time with it.
Although I can *do* all sorts of math, explaining it is another matter.
I've been trying to use the kids' blocks and other visual/tactile aids, but
I'm sort of stuck on a language issue and hoping someone here might have an
idea of a better way to explain it.  It has to do with the way we talk about
performing operations on both sides of an equation, a concept that continues
to mystify her.

Let's say we're converting 0.4545_ (repeating) from a decimal to a fraction.
So we start with this:

N = 0.4545_

I say to her, "We'll multiply both sides of the equals sign by 100, in order
to get the repeating digits to the left of the decimal place."  This sounds
just terrific to her, and I write this:

100N = 45.4545_

And she objects, saying that I didn't *really* multiply the left side of the
equation by 100.  And it's true, I didn't actually perform the
multiplication.  But she doesn't get it.  Why call it multiplying if you
don't really do any multiplication on the left side?

I'm at a loss for how to use clearer language on this notion of performing
the same operation on both sides of the equation...  Any suggestions?

The rest of the conversion problem is left as an exercise for y'all.  The
answer is 5/11... and I point out that the fraction expresses a division
that you don't actually calculate, but that doesn't help.

Obtuse explanations or suggestions to do the problems a different way
probably won't help.

Nick Arnett
Phone/fax: 408-904-7198

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