OK, so the original prices range from 175$ to 260$. This can be represented by a compound inequality like this:
175 ≤ price ≤ 260
Got that? it can cost up to (and include) 260, or be a little as 175$.
With a 30$ rebate, it can cost 30$ less (total), so both the most expensive and least expensive printers will cost 30$ less. Subtract 30 from both sides to get this:
145 ≤ final price ≤ 230
tada! he can expect to spend somewhere between 145 and 230 dollars.