Question

An equilateral triangle has sides of length 5.1 cm,correct to one decimal place.calculate the upper and lower bounds for the perimeter of the triangle

Answer 1

For side length s, s(max) =16.149* cm and s(min) = 16.05 cm, where * denotes a repeating digit 

In an equilateral triangle, perimeter p = 3s. Hence p(max) = 48.449* cm and p(min) = 48.15 cm 

To the nearest millimeter, p(max) rounds to 48.4 cm and p(min) is 48.2 cm