How many superficial feet arc contained in a boiler 23 feet in length and 5 ½ feet in width ?

Set 1 on b to 23 on A; and against 5.5 upon b is 126.5 square feet upon a. If 5 square feet of boiler surface be sufficient for each horse-power, how many horses' power of engine is the boiler equal to ?

Set upon b to 126.5 upon a; and against 1 upon B is 25.5 upon A.