Electromagnetic waves travel at the speed of light, which is 299,792,458 meters per second (c) (our constant), and for you old school people, that’s 983,571,056.43 feet per second (186,282.39 Miles per second).
The correct symbol for wavelength is the Greek letter Lambda (λ) but for ease of thought we will use (w)
And finally, a simple one for Frequency (f)
frequency (f) = constant (c) / wavelength (w)
f = c / w
wavelength (w) = constant (c) / frequency (f)