Metric to English measurements - no more precision

Here's an excerpt from a CNN report about the airplane crash: "The part of the ocean where the debris and bodies have been found ranges between 19,685 and 26,247 feet (6,000 and 8,000 meters) deep. The search area covers 77,220 square miles (200,000 square km), an area nearly as big as the country of Romania."

Converting 6000 meters to feet doesn't change from 1 to 5 digits of precision, and similarly for the other numbers.

This happens in all sorts of reporting. Why isn't it taught as part of Journalism 101?