math
posted by mark on .
Laura is a salesperson in a retail store and earns $65 per week plus 10% of her weekly sales. If Laura earned $200 one week, what were her sales that week

200=65+.10x
She earns a flat salary of 65 weekly no matter what. Her commission is 10% and is a reward for her to sell more. 200 is her total. x is what you want to know.
Subtract 65 from both sides.
135=.10x
Divide both sides by .10
x=$1350 in sales that week 
Your commission is $60 for
every $200 sold.
Commission on $700 =