What is the math formula in finding the radio frequency of and magnic field

Wavelength(λ)= velocity(c) / frequency(f) :[m] = [m/s] / [Hz].
Frequency(f) = velocity(c) / wavelength(λ):[Hz] = [m/s] / [m].
velocity(C)= wavelength(λ) * frequency(f) :[m/s] = [m] * [Hz].
c = 3*10^8[m/s].