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Independence and Dependence
When are events independent of each other? Sampling with and without replacement.
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problem
World of Tan 13 - A Storm in a Tea Cup
7 to 11
Can you fit the tangram pieces into the outlines of the convex shapes?
problem
World of Tan 10 - Butterflies
7 to 11
Can you fit the tangram pieces into the outline of the butterfly?
problem
World of Tan 9 - Animals
7 to 11
Can you fit the tangram pieces into the outlines of the camel and giraffe?
problem
Arranging the Tables
7 to 11
There are 44 people coming to a dinner party. There are 15 square
tables that seat 4 people. Find a way to seat the 44 people using
all 15 tables, with no empty places.
problem
How Confident Are You?
11 to 16
What proportion of people make 90% confident guesses which actually contain the correct answer?
problem
Impossible Picture?
14 to 16
Under what circumstances can you rearrange a big square to make three smaller squares?
problem
The Ultra Particle
16 to 18
Explore the energy of this incredibly energetic particle which struck Earth on October 15th 1991
problem
Favourite
Triangle Numbers
11 to 14
Take a look at the multiplication square. The first eleven triangle numbers have been identified. Can you see a pattern? Does the pattern continue?
problem
Favourite
Watch the Clock
7 to 11
During the third hour after midnight the hands on a clock point in the same direction (so one hand is over the top of the other). At what time, to the nearest second, does this happen?