Two-digit numbers on interstate signs indicate which of the following?

Two-digit numbers on interstate signs indicate which of the following?

• A. Two-digit Even numbers indicate East-West; two-digit Odd numbers indicate North-South
• B. Two-digit Even numbers indicate North-South; two-digit Odd numbers indicate East-West
• C. Three-digit numbers indicate East-West
• D. One-digit numbers indicate direction

Answer: (A)

Two-digit interstate numbers follow a simple rule: even numbers run primarily east–west, while odd numbers run primarily north–south. This creates a grid-like system that helps you gauge direction just from the number. For example, even two-digit routes like I-10 and I-40 traverse the country mainly east–west, while odd two-digit routes like I-95 or I-75 run mainly north–south. Three-digit interstates are typically auxiliary routes (beltways or spurs) tied to a primary two-digit highway, not used to indicate direction. One-digit interstates aren’t used to indicate direction on signage.

Two-digit interstate numbers follow a simple rule: even numbers run primarily east–west, while odd numbers run primarily north–south. This creates a grid-like system that helps you gauge direction just from the number. For example, even two-digit routes like I-10 and I-40 traverse the country mainly east–west, while odd two-digit routes like I-95 or I-75 run mainly north–south. Three-digit interstates are typically auxiliary routes (beltways or spurs) tied to a primary two-digit highway, not used to indicate direction. One-digit interstates aren’t used to indicate direction on signage.