An odd-numbered route indicates a route that runs in which direction?

• A. Runs east and west
• B. Circles the state
• C. Runs north and south
• D. Runs diagonally across

Answer: (C)

Odd-numbered routes are designated for those that run primarily north-south. The numbering follows a simple rule: as you move eastward across the country, the odd numbers get larger, signaling a north-south corridor. Think of I-5 along the West Coast and I-95 along the East Coast—both run mostly north-south. Even-numbered routes, on the other hand, run mainly east-west, with lower numbers toward the south and higher numbers toward the north (for example, I-10 in the southern U.S. and I-90 in the northern U.S.). So an odd number indicates a north–south orientation, not a circuit around a state or a diagonal path.