A transportation agency has one 38-seater bus and some 13-seater buses. They have enough seats to board no more than 417 passengers on their buses. Which inequality represents the possible number of 18-seater buses they have.
Ov12

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.

Then just do it (lol)