We should equal the average depth to 1, so if it raises 3%, it raises 0.03. Simply add the original (1) plus what it rose (0.03) and multiply the original by that, so 8.3 × 1.03 = new depth. The result is 8.549 feets.
If you multiply any irrational number by the rational number zero, the result will be zero, which is rational. Any other situation, however, of a rational times an irrational will be irrational.
