#!/usr/bin/env python2

volt = 3.5
inp = 75.0
a = 267.0
b = 554.0

black = (inp*a)/(inp+a) / (b + (inp*a)/(inp+a)) * volt
grey = (inp*b)/(inp+b) / (a + (inp*b)/(inp+b)) * volt
white = inp / (inp + (a*b)/(a+b)) * volt

print "Black: %fV (nominal 0.3V)" % black
print "Grey: %fV" % grey
print "White: %fV (nominal 1V)" % white