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Losing It
  Teaching Guide

Activity 2: Grades 5-8
Puzzle Solving

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Magic Triangle Answer
There are several combinations that will work. Here's one that works using the side sum of nine.

Pizza By the Slice
Imagine a large round pizza that has just come out of the oven. Using only three cuts, how can you divide this pie into eight equal pieces? HINT: Don't worry about the mess!

Use your knife to cut the circular pie in half along its diameter. Then, stack one half on top of the other. Divide the half circles with a single cut through two layers. Now, stack all four wedge-shaped sections together. A single cut through the middle of the stack creates eight, equal-sized slices.

Toothpick Tricks Answer
Position toothpicks in the pattern shown here. Remove six toothpicks and leave only three complete squares behind. HINT: the squares can be of any size.

More Toothpicks Answer
You need to constuct a 3D pyramid structure with one of the original triangles becoming the pyramid's base. The remaining three toothpicks form the edges of the three vertical sides that rise up from the desktop.

Measuring Mania Answer
Fill the 3-cup container with water. Pour this water into the 5-cup container. Again fill the 3-cup container with water. Pour this water into the 5-cup until it fills with water. The water volume that remains in the 3-cup container is equal to exactly one cup.

Moldy Math Answer
Day 27. Since it doubles size every day, on the day prior to covering the whole surface, the mold encrusted half the surface.

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