So, a bit of a stumper yesterday, huh? Seems the best way to play would be Quantum - Prod - Quantum. Since he claimed he'd definitely win two in a row, it is imperative that he win the second game, and thus that he play Prod second. that way, even if he loses the first one, he has a chance at making good on his boast.

Something a little easier, perhaps:

When Sandy Beach was six years old, she hammered a nail into her favourite tree to mark her height. Ten years later, at sweet sixteen, Sandy returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?