🔍 Key Concepts

• Using the tide tables for Port of Spain, Trinidad, for 5 March 1983 • Finding the two surrounding tidal heights and times that bracket 2.5 feet (0.76 m) • Applying proportional (linear) interpolation in time between those two known heights

💭 Think About

• Which high or low tide events in the table for that date are closest to 2.5 feet, and is 2.5 feet between a rising or falling tide? • Once you know the times and heights just before and just after 2.5 feet, how do you set up a proportion to find what fraction of the time interval has elapsed? • After you find the interval after 0300 when the height is 2.5 feet, how do you add that interval to 0300 (ZD +4) to get a clock time?

✅ Before You Answer

• Confirm the correct tide table entries (times and heights) for Port of Spain on 5 March 1983 before interpolating • Make sure you are interpolating between the right pair of tide heights (one less than 2.5 ft and one greater than 2.5 ft) that occur after 0300 • Double-check your time addition from 0300, including minutes, so the final time matches one of the choices exactly