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Logical Reasoning

If all of the statements are true, where is the gold?

There is gold in only one of the chests. If only one of the messages is true (and the other two are lies), where is the gold?

In the previous two problems, we were given imperfect information and had to come up with creative ways to use the information given to solve the problem.

In this chapter, we explore the idea through many math problems that require this mix of creativity and logic.

From the above diagram, we see that in order to create 1, 2, 3 and 4 unit equilateral triangles, we need 3, 5, 7 and 9 matchsticks respectively.

What is the minimum number of matchsticks needed to create 7 unit equilateral triangles?

In the above image, there are 2 squares of different sizes.

What is the minimum number of matchsticks that we have to move, to create 3 squares?

Note: The 3 squares could be of different sizes.

What is the minimum number of matchsticks that can be removed to leave three congruent, non-overlapping squares?

Note that every remaining matchstick must be part of a square.

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