Question 202783
The area of the square cardboard (1.2X1.2)m. or (120X120)cm. is:
{{{A = (1.2)^2}}}sq.m. or {{{(120)^2 = 14400}}}sq.cm
{{{A = 14400}}}sq.cm.
The area inside of the border is:
{{{a = (120-20)(120-10)}}}
{{{a = (100)(110)}}}
{{{a = 11000}}}sq.cm. Subtract the inside area from the entire area.
{{{highlight(14400-11000 = 3400)}}}sq.cm. This is the area of the border.