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Logic puzzles
Textbook: Part 3, pp. 98–99
GoalSolve logic puzzles with drawings, tables and calculation; find patterns.
New words
logic puzzle · mantiqiy masalapattern · qonuniyatstaircase · zinapoyaVenn diagram · Venn diagrammasi
Explanation
In a logic puzzle we first think, then draw a picture, a diagram or a table. To find a pattern we look at the difference between neighbouring numbers: 753, 749, 745, 741 – each time 4 less. In a Venn diagram, where two circles overlap, the overlap belongs to both. Then those in both = first + second − all.
Worked examples
753, 749, 745, 741, ... – the next numbers are 737 and 733.
Of 12 friends, 10 play football and 8 play basketball, so 10 + 8 − 12 = 6 do both.
Class activity
“Logic hour”: each team solves one logic puzzle and explains the solution to the class with a diagram. The team with the clearest explanation scores.
Practice
1
Find the pattern: 753, 749, 745, 741, ... What is the next number?
737
2
A staircase has 8 steps. Going from one floor to the next takes 2 staircases. How many steps are climbed from floor 1 to floor 3?
32
3
Temur has 14 friends, all in clubs: 9 in art and 8 in dance. How many are in both clubs?
3
4
New York is (for this puzzle) 9 hours behind Tashkent. When it is 15:00 in Tashkent, what time is it in New York?
6
5
9 craftsmen were paid with 10 identical bags of coins. Each got 1 bag and 4 more coins. How many coins are in one bag?
36
6
Aziz is Sherzod’s son and Sherzod is Muslim’s son. Who is Aziz to Muslim?
Grandson