Triangle ABC is an equilateral triangle with side 4 cm long which is measured corrected to the nearest cm. Find the percentage error of the perimeter of triangle ABC. 3. The attempt at a solution Is [(0.5 x 2 x 3) / 12] x 100% correct? the '2' here is the measurement errors of the starting pt and ending pt of line segment. or it should be: [(0.5 x 3) / 12] x 100% plz help~!