split the two questions ... a colour? a tool? For normal human beings, only a few combinations would come up. Try thinking the other way... You wont find yourself knowing lots of tools unless you are an expert... And you wont have many colour that come up in your mind in 1-2 seconds .... This is why people would come up with an similar answers. Most specifically, the mathematical calculations are here to avoid those who wants to be an idoit and try to come up with an different answers so that they are seen as special .... So if u now try to get someone to do the same question without being asked to work out the calculations at the beginning, the answer will be AT LEAST much LOWER than 98% as it is suggested . !!!!! 30-40 % I would say or even lower than that !!!!