If you use the Triangle Inequality Theorem, it states that the sum of 2 sides of the triangle would equal more than the third side. So three triangles can be made with those side lengths.
7.5 mph in 3 hours the train can travel 22.5 miles. Take 2.5 and times it by 3 to get the mph, then multiply that answer by 3 again to get the total miles in 3 hours
