The Three-Jugs Problem

Using jugs A, B, and C with the capacities shown, how would you measure out the volumes indicated?

The Three-Jugs Problem

Problem A B C

Given jugs of these sizes: Measure out this much water:

1

2

3

4

5

6

7

21 127 3

14 46 5

18 43 10

7 42 6

20 57 4

23 49 3

15 39 3

100

22

5

23

29

20

18

The Three-Jugs Problem

Solution: All seven problems

can be solved by the same equation: B-A-2C

But simpler solutions exist for problems 6 and 7, such as A-C for problem 6.

Number Puzzle

Figure out the pattern for the following sequence of numbers:

8, 5, 4, 1, 7, 6, 3, 2, 0

Finish the Sequence

O - T - T - F - ? - ? - ?

J - F - M - A - ? - ? - ?

Mental Set Questions

1) Explain how a mental set was an obstacle to solving the Three-Jugs problem.

2) Explain how a mental set was an obstacle to solving the Number Puzzle.

3) Using the idea of a mental set, why were the 2nd and 3rd sequences so much easier to solve than the 1st?

4) Give a real-world example where a mental set has made it difficult to solve a problem.