let the width of the field = x.
Then the length = 4x
Now the perimeter = 2 * length + 2 * width, so we have the equation:-
2*4x + 2x = 340
8x + 2x = 340
10x = 340
x = 34 yards = width
4x = length = 136
Answer: the width is 34 yards and length is 136 yards.
