# Joan sold half of her comic books and then bought 8 more. She now has 15. How many did she begin with?

##### 1 Answer
Nov 1, 2016

$14$

#### Explanation:

Let's construct an equation for the question and solve it

Let the number of comic books that Joan had in the beginning is $x$

In the start she sold half her books (so,multiply by $\frac{1}{2}$)

color(red)(x*1/2

Next, she bought $8$ more books (so,add $8$)

color(red)(x*1/2+8

At the last she has $15$ books (so,let the equation equal $15$)

color(red)(x*1/2+8=15

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Now let's solve the completed equation

$\rightarrow x \cdot \frac{1}{2} + 8 = 15$

Subtract $8$ both sides

$\rightarrow x \cdot \frac{1}{2} + \cancel{8} - \cancel{\textcolor{v i o \le t}{8}} = 15 - \textcolor{v i o \le t}{8}$

$\rightarrow x \cdot \frac{1}{2} = 7$

Multiply both sides by $2$

$\rightarrow x \cdot \frac{1}{\cancel{2}} \cdot \cancel{\textcolor{v i o \le t}{2}} = 7 \cdot \textcolor{v i o \le t}{2}$

color(green)(rArrx=14

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So Joan started with $14$ comic books

Hope this helps !...

:)