The class is about heat, waves, and light. The website wants exactly the perfect answer and in the same metric system units that are stated on the calculators that are on the picture for the question, if not, it'll mark it wrong.

Set 18 Problem 5 A single slit of width 0.0196 mm is illuminated by two monochomatic wavelengths. [f the 3rd diffraction minimum of 605 nm light coincides with the 5th diffraction minimum of the other wavelength, what is the other wavelength