4173 POWs

Three penguins - Perky, Waddles, and Tux - all go to the Antarctic Amusement Park. The new ride, called the Crevasse, is very exciting. Unfortunately, there is a weight limit of 110 pounds for the ride. The three penguins want to ride together, but aren't sure it will be safe.

Since the scale can hold only two penguins at a time, it is hard for them to figure out the weight of all of them together. (Being very social birds, they don't want to get on the scale alone.)

Class 3

Olympic Rings Repair - posted September 25, 2000

Jellybean and I have been watching the Sydney 2000 Olympics, wishing we were in Australia! We both hope to attend an Olympics someday. Jellybean suggested we have a party to celebrate the accomplishments of all the athletes and participate in the international spirit of the Olympics.

Jellybean created an Olympic rings decoration and was about to put it up when I ran into her. Jellybean was left holding the blue ring, but the yellow, black, green, and red rings had come apart and rolled to various spots in the room.

I quickly apologized for my lapse in attention and helped her put the rings back together. We were careful to put the colors in the proper order.

After we had completed the repairs and had hung the decoration on the wall, Jellybean asked me how many different ways there are to arrange the colors while keeping the same formation for the Olympic rings. I'm hoping you'll help us find the answer to her question.

Bonus: Generalize your results above for other combinations (if you noticed a pattern, how would it extend to the 6th, 7th, 10th, and 100th rings?).

Class 4

Meters of Money - posted March 5, 2001

Ms. Juncos's students have just completed a unit on the Canadian Mint. As a transition to their next unit on the Measurement, Ms. Juncos is having them create meters of money. The students are very excited about bringing in loose change to create the meters of money, and they have suggested that the completed stacks be donated to a local homeless shelter as part of their community service project.

Since it will take more than one day to collect the necessary coins, the class has elected four members as temporary treasurers. Charlotte Barnum will be in charge of the penny stack, Winifred Edgerton the nickel stack, Ruth Gentry the dime stack, and Ida Metcalf the quarter stack.

What is the minimum amount of money that will have been donated when all four stacks have reached a meter in height?

Bonus: The names of the treasurers were chosen because of Women's History Month (October in Canada, March in the US). I hope you will take some time to discover what they have in common. For bonus credit, I'd like you to find out how many dissertations Sofia Kovalevskaya had to write before becoming the first woman to receive a Ph.D. in mathematics. Be sure you cite your source and write your findings using complete sentences.

Class 5

Mystery Numbers - posted January 11, 1999

A few archaeologists were digging for a lost tomb when they found the entrance. Inside there was an old scroll with numbers on it. Through the years in the cold, damp tomb, some of the numbers had disappeared (they have been "replaced" by letters in the diagram below to help you in your explanation).

7	5	12	3	(A)	8	4	(B)	(C)
5	4	9	1	8	(D)	(E)	2	4
2	1	3	2	7	(F)	1	(G)	2
10	4	(H)	2	(I)	15	3	14	8

4173 -- Elementary Mathematics Methods

Problems of the Week