posted by Lisa .
The lengths of the sides of a triangle are 3,5, and 7 inches. How many inches long is the shortest side of a similar triangle that has a perimeter of 75 inches?
given triangle has perimeter 3+5+7 = 15
75 is 5*15, so all the sides have to be scaled up by 5. The smallest would thus be 5*3 = 15