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Three GiftsTo Play With....

[Gift 1] A restaurant, whose owner is a puzzle fiend, was going to close for vacation. The note on the door read: "This is being posted on Sunday. We will be closed for two week's vacation from the day after two days before the day after tomorrow."

What day of the week did the restaurant close?

[Gift 2] A ferryboat is full when it has ten cars on board. It is also full when it has six trucks on board. The ferryboat never carries cars and trucks at the same time. The ferryboat made five trips across the river and was full each trip. It carried a total of forty-two cars and trucks across the river. How many cars did the ferry carry all together in its five trips?

[Gift 3] Stu Dent used to spend all his time dreaming about getting rich, even saying "I'd do anything to be rich." So, his math teacher offered to make Stu rich.

"See this line?" she said, while drawing a chalk line across the classroom floor. "Just walk across it and I will double the money you have now. In fact, each time you cross I will double your money. There is just one more thing...you must give me $24 after each crossing."

Stu agreed, he crossed the line, stopped to count his money and, sure enough, it had doubled. Stu paid his teacher $24 and crossed the line a second time. Again his money was doubled. Stu paid another $24 and crossed a third time. Again his money had doubled but this time there was only $24 left which he had to pay the teacher, so Stu was left with nothing. The teacher laughed....and erased the chalk line.

How much money did Stu Dent start out with?

Note: Try to generalize this last problem to the case of N total line crossings and $M paid each time to the teacher.


Hint: Sorry, the problems were your only gifts...


Solution Commentary: No commentary...keep playing.