Which sequence correctly describes how to determine the OT factor?

Which sequence correctly describes how to determine the OT factor?

• A. Divide the distance from the observer to the target by 1000; round to the nearest whole number; if the decimal is .5, round to the nearest even; and if the distance is less than 1000 express OT factor as decimal
• B. Multiply the distance by 1000; round to the nearest whole; if decimal is .5 round up; always express OT factor as a whole number
• C. Add 1000 to the distance; round to the nearest ten; always express OT factor as a decimal
• D. Divide by 100; round to the nearest whole; if decimal is .5 round down; express as decimal when distance > 1000

Answer: (A)

When determining the OT factor, you convert the observer-to-target distance from meters into kilometers by dividing by 1000. If the distance is at least 1 kilometer, you express the OT factor as a whole number after rounding to the nearest kilometer, using bankers rounding: if the fractional part is exactly .5, you round to the nearest even number. If the distance is less than 1 kilometer, you keep the OT factor as a decimal to reflect the precise sub-kilometer value. For example, 2.6 km becomes 3 after rounding, 2.5 km becomes 2 (because 2 is even), and 0.9 km stays as 0.9 rather than rounding to 1. This approach standardizes reporting across ranges and helps keep calculations unbiased over many observations. The other options don’t fit because they apply the wrong operation (multiplying by 1000, adding 1000, or dividing by 100) and would produce incorrect units or rounding behavior.

When determining the OT factor, you convert the observer-to-target distance from meters into kilometers by dividing by 1000. If the distance is at least 1 kilometer, you express the OT factor as a whole number after rounding to the nearest kilometer, using bankers rounding: if the fractional part is exactly .5, you round to the nearest even number. If the distance is less than 1 kilometer, you keep the OT factor as a decimal to reflect the precise sub-kilometer value.

For example, 2.6 km becomes 3 after rounding, 2.5 km becomes 2 (because 2 is even), and 0.9 km stays as 0.9 rather than rounding to 1. This approach standardizes reporting across ranges and helps keep calculations unbiased over many observations.

The other options don’t fit because they apply the wrong operation (multiplying by 1000, adding 1000, or dividing by 100) and would produce incorrect units or rounding behavior.