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### Price Plus 1/2 Price

```
Date: 12/05/2001 at 21:20:41
From: Michelle
Subject: Math problems - critical thinking

A puzzle book costs 5.00 plus one-half of its price. How much does
the puzzle book cost? (It is not \$7.50.)
```

```
Date: 12/05/2001 at 22:06:19
From: Doctor Ian
Subject: Re: Math problems - critical thinking

Hi Michelle,

This is one of those cases where variables come in really handy.

We're looking for a price. We don't know what it is, but we can give
it a name:  P.

The price of the book is \$5 plus one-half the price.

\___________________/            \________________/
P             =  5  +       (1/2)*P

Can you take it from here?

(Note that, as if often the case in puzzles like this, there is a way
to 'see' the answer without doing any computations at all.  If the
book costs \$5 plus 1/2 its cost... then \$5 must be the _other_ half of
its cost.)

- Doctor Ian, The Math Forum
http://mathforum.org/dr.math/
```
Associated Topics:
Middle School Algebra
Middle School Word Problems

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