First you'd change the 68 yards to 194 feet. then you would make the equation (3x-2)+(3x-2)+x+x=204 because the length is 2 feet less than 3 times the width (x). when you combine like terms it is 8x-4=204. then you'd move the -4 over to the 204 to make it 8x=208. x=26 feet. then you plug it back in time find the length is 76 feet.
If you take 369 divided by 410 it gives you 0.9 which is equal to 90% which then leads us to realized that if 369 is 90% of 410 then the discount would have to be 10%