An equilateral triangle has sides of length 2 units. A second equilateral triangle is formed having sides that are of the length of the sides of the first triangle. A third equilateral triangle is formed having sides that are of the length of the sides of the second triangle. The process is continued until four equilateral triangles exist. What will be the percent increase in the perimeter from the first triangle to the fourth triangle? Express your answer to the nearest tenth.

mathbum
Sep 9, 2018

#1**+1 **

1st triangle perimeter = 2 + 2 + 2 = 6

2nd 6+6+6 =36

3rd 36+36+36 = 108

4th 108+108+108 = 324

% increase = (324-6)/6 x 100 = 5300%

This answer will likely cause some controversy, but think of it this way

if something is TWICE as big it is 100% bigger than the original ( 12 is twice as big as 6 100% increase from 6 is 12)

if something is THREE timeas as big as the original it is 200% bigger ( 18 is three times as big as 6 200% increase from 6 is 18).......

ElectricPavlov
Sep 9, 2018