october 26

• Continue choosing the position for a bus stop. How democracy works?
• Robot in a labyrinth
• Adding vectors
• Experiment: ball in a round glass

Homework:

1. Draw three vectors:

• A at (0, 0) 
• B at (0, 5) and
• C at (3, 4).

Which is further away from A: B or C?

2. Diza has a drawer with 4 green, 4 blue and 2 red socks.  She reaches inside, not looking, and grabs some socks. How many should she get, to be sure there are at least two socks of different colors?

3. Plastic container floats in a dish, so that the water level is an inch below the rim of the dish. If you move some of the water from the dish to the container, will the water level go up? down?

october 19

homework

• Where to place a bus stop so that the total walk for the people in the village is the least?

• Can you find all ways to choose two colors out of 6?

• It is easy to get a triangular shadow out of a tetrahedron. Can you get a square shadow?

october 12

Write numbers 1...9 so that any two neighbors were at most 2 apart and 9 is in the middle.

Diza has in her box red, blue and green socks. She never puts on socks of the same color. How many ways are there for her to choose her socks? If she has B, R, G and Y?

Envelopes for the cube

Envelopes for the tetrahedron...

Midpoints of vectors...

hopscotch! making the cupcake fly. Did not do today: vectors won.

Homework

1. In a box there are 5 pencils, Red, Blue, Green, Yellow and Orange. Joan wants to choose three of them. How ways are there to choose them?

2.

Mark on graph paper three vectors:

• A(3,3);
• B(-3,1)
• C(1,-3)

Draw the midpoints between A and B, B and C, C and A.