A blonde woman goes into an electrical shop to buy a tv. She gets the attention of the sales assistant and says to him, `I want to buy that tv`. He tells her, `sorry we dont sell to blondes`. So she goes home and dyes her hair brunette. The next days she asks him again, and again he says, `sorry we don’t sell to blondes`. So she goes home and dyes her hair red this time. She goes back the next day and asks him again, and once again he says, `sorry we don’t sell to blondes`.
A little confused now the blonde woman asks him `how do you know that I am blonde?`
He turns to the woman and says `I know you’re blonde because that’s not a tv, its a microwave`