- Thread starter
- #1

#### bergausstein

##### Active member

- Jul 30, 2013

- 191

i solved this problem in two ways by 1st choosing the unknown represent the number of $\$10$ bills and 2nd by choosing the unknown represent the number of $\$20$ bills.

and i got these answers from my two methods, $14$ $\$10$ bills, $8$ $\$20$ bills and $32$ $\$5$ bills.

on my third method i chose the unknown represent the number of $\$5$ bills.

and here how it goes,

let $x=$ number of $\$5$ bills,

$\frac{x}{2}-4=$ number of $\$10$ bills

$\frac{x}{2}-4-6=$ number of $\$20$ bills

$5x+10\left(\frac{x}{2}-4\right)+20\left(\frac{x}{2}-10\right)=460$

$5x+5x-40+10x-200=460$

$20x-240=460$

$20x=700$

then, $x=35$ ---> from here the number of $\$5$ bill is bigger than my previous result. can you pinpoint where is the mistake here? thanks!

p.s use only one variable.