Answer:
Final displacement with respect to the starting position is 832.37 meter
Explanation:
Lets consider that the orienteer start to run on the point of (0,0) point of a coordinate system. When he runs towards to east side about 400m, he will be at the point A(400,0). After he runs to the northeast (at a 45 degree angle from due east and from due north), approximately he will make 353.55 meter to east and 353.55 meter to the north side and he will be at the point of B(753.55, 353.55)
From the starting point total displacement will be 832.37 meter. Please check the attached graphical solution.