Use symbols to represent unknowns and variables. Write inequalities to answer questions arising situations.

1. A sales representative is given a choice of two paycheck plans. One choice includes a monthly base pay of $300 plus %10 comission on his sales. The second choice is a monthly salary of $1200. For what amount of sales would the representative make more money with the first plan?

2 answers

0.1x > 900
x > 900/0.1
x > $9,000
I don't understand where 900 comes from...