I am using a pressure sensor that gives me .2V to 4.8V from 0 to 6 KPA

I want to convert that firstly into mm H20 and then mm H2O to Knots. The first bit is easy. The equation for the mm H2O to knots is 7.7538*(mmH2O ^ .5).

That where I am having the trouble with no FP Math

All ideas welcome

aajgss