If the forward azimuth is 120°, what is the back azimuth?

If the forward azimuth is 120°, what is the back azimuth?

• A. 300°
• B. 120°
• C. 240°
• D. 360°

Answer: (A)

The back azimuth is the direction exactly opposite the forward azimuth, 180 degrees away. To find it, add 180 degrees to the forward azimuth and wrap around if it goes past 360. For a forward azimuth of 120 degrees, adding 180 gives 300 degrees, which stays within 0–360, so the back azimuth is 300 degrees. The other numbers don’t fit because they don’t point in the exact opposite direction: 120 degrees is the same direction as the forward azimuth, not opposite; 240 degrees is not 180 degrees opposite of 120 degrees; and 360 degrees corresponds to due north, not the opposite of 120 degrees.

The back azimuth is the direction exactly opposite the forward azimuth, 180 degrees away. To find it, add 180 degrees to the forward azimuth and wrap around if it goes past 360. For a forward azimuth of 120 degrees, adding 180 gives 300 degrees, which stays within 0–360, so the back azimuth is 300 degrees.

The other numbers don’t fit because they don’t point in the exact opposite direction: 120 degrees is the same direction as the forward azimuth, not opposite; 240 degrees is not 180 degrees opposite of 120 degrees; and 360 degrees corresponds to due north, not the opposite of 120 degrees.