🔍 Key Concepts

• Mid-latitude sailing formulas: using distance and course to find change in latitude and departure • Relationship between departure, mid-latitude, and change in longitude • Sign and direction: how course quadrants affect whether latitude/longitude increase or decrease

💭 Think About

• From a course of 083°T, decide whether you are going mainly north/south or east/west, and whether your latitude should increase or decrease from the starting latitude • Use the distance and course to find the change in latitude in minutes; then add/subtract it correctly from the starting latitude and see which options match • Once you have the departure, apply the mid-latitude formula for change in longitude and decide whether the longitude value should get numerically larger or smaller in the western hemisphere

✅ Before You Answer

• Confirm you used ΔLat = Distance × cos(Course) and Departure = Distance × sin(Course) with distance in nautical miles • Be sure you computed mid-latitude correctly (average of initial and final latitude estimate) before converting departure to ΔLong • Check that your final latitude and longitude are both in the correct direction (north/south and east/west) before matching to the choices