I am making the $50 robot, and was going on to the photo sensors. The problem is the largest sensors in bright light give me my lowest resistance of around 10 Kohm. When using the equation, even if I use the bright light resistance twice, I am getting that I need a resistor of around 10 Kohm (Since it would be the square root of 10 squared), which is drastically more then what was suggested if you aren't testing them, and drastically more then the resistors I already bought. Are my photo resistors wacky? Am I doing this basic math wrong? Should I just slap on the 1.6 Kohm resistor I already have and run with it? I cannot figure this out.