FRATERNITY/TOGA PARTY SMARTS: "I need a mathematician to be my assistant", - says the fraternity instructor dressed in a toga. In fact all the fraternity party guests can be dressed in togas."His/her task is very simple: I shall enumerate different numbers. My assistant's task is to name the numbers more by one than the numbers I name. Such as If I say "eight", the assistant must say "nine". If I say "thirty - two" the assistant must say "thirty three" etc. Who can "cope with this task?" The instructor names the increasing numbers. The numbers increase by tens and hundreds. Every time the assistant confidently names the numbers by one more. The counting continues until the instructor names number "4099". At this number, the assistant will make a mistake. Instead of "4100" he/she will say "5000".