I think I saw that you tried to include that your units were in inches. this is not a metric unit to start. convert inches to centimetres. then multiply the length by the width to get your answer in cm^2, a metric unit
The metric unit of the meter would be the appropriate measure of the area of classroom. Calculating area involves multiplying the length (in meters) of the classroom's length and width. Area of the classroom would be in square (^2) meters.
The basic unit of area in the Metric System is the ar, a unit equal to 100 square meters. However for most practical purposes the nonstandard unit of area is the hectare, which is 100 ares or 10,000 square meters.
The metric unit of mass is the kilogram. The metric unit of length is the meter. The metric unit of time is the second. The metric unit of electric charge is the coulomb. All other units are combinations or multiples of these.