Hi, I'm having trouble with a word problem. I'm not sure how to solve it:

Tom and Alison are both salespeople. Tom's weekly compensation consists of $300 plus 20 percent of his sales. Alison's weekly compensation consists of $200 plus 25 percent of her sales. If they both had the same amount of sales and the same compensation for a particular week, what was that compensation, in dollars? Answer: 700

Question

Hi, I'm having trouble with a word problem.  I'm not sure how to solve it:

Tom and Alison are both salespeople. Tom's weekly compensation consists of $300 plus 20 percent of his sales. Alison's weekly compensation consists of $200 plus 25 percent of her sales. If they both had the same amount of sales and the same compensation for a particular week, what was that compensation, in dollars?   Answer:  700

phi · Answer

Tom's weekly compensation consists of $300 plus 20 percent of his sales.
20% is the same as 0.20   or 20/100 or 2/10  or 1/5
300 plus 20% of sales  means:
300   +    1/5 * S

Can you make this into an expression:
 Alison's weekly compensation consists of $200 plus 25 percent of her sales