Answer:
The shortest possible length is 400 yards
Explanation:
To find the shortest possible length of the third side, we apply the triangle equality theorem
This states that the sum of two of the sides of a triangle must be greater than the third side for us to have a triangle being formed
Since we must have a multiple of 100, the next multiple of 100 greater than 600 is 700
So we simply subtract 300 from this so that we can get the possible length of the third side
Mathematically, this will be;
700-300 = 400