Which statement is true regarding grid accuracy categories?

• A. A 6-digit grid is more precise than a 4-digit grid.
• B. A 4-digit grid is more precise than a 6-digit grid.
• C. They have the same level of precision.
• D. Neither uses metric measurements.

Answer: (A)

Grid precision increases as you add more digits because each extra digit narrows the mapped area. A 4-digit grid reference pins you to a 1,000-meter (1 kilometer) square on the map, giving a broad but useful location. A 6-digit grid reference adds one more digit for the easting and one for the northing, slicing that 1-kilometer square into 100-meter squares and thus locating you ten times more precisely. These coordinates are expressed in meters, so the 6-digit reference provides higher precision than the 4-digit one. That’s why the statement stating that a 6-digit grid is more precise than a 4-digit grid is true. The other options don’t fit because the 4-digit reference is not more precise, they don’t have the same precision, and both systems use metric measurements.