Area is just height times width so if it’s a square all sides are equal so you do 3 2/7 time 3 2/7 and get 10.796 in^2
The answer to your problem would be 400 because to find the answer you need to multiply 120 by .3 to get the answer because 3 % means per 100 and that is why you make it .3 hope i help.
-x + -x-1 + -x-2 = -204
-3x=-201
x=-67
-67-68-69=-204