Hello. my robot requires an 18k resistor at one point. my problem is that I don't have one and my radioshack has never heard of it. anyway, I was wondering on how to create one. I know that adding in a series circuit it's just R1+R2... and I think that parallel circuits add with the reciprocal. so how can one get an 18k. Someone told me that I could make a parallel circuit with a 22k and some 1ks, but I don't think that would work. I know that I could create one in a serial circuit, but that might take a lot of resistors. thanks for the help.