Logical 'imbalance' puzzles

Here's something for all of us puzzle lovers: logic imbalance problems invented by Paul Salomon (HT Denise). You need to order the shapes by their 'weight':


Imbalance 4
Which shape is the heaviest? Which is the second heaviest?
Picture by Paul Salomon 

Think logically - or write down some inequalities and use algebra. Pretty cool. They are simple, yet captivating. A new, creative idea! Paul also recommends you start making your own imbalance puzzles, as a more 'puzzling' exercise.

Comments

Malcolm Kirkpatrick said…
I used sketches of a pan balance to teach solving linear equations in one variable, then pan balance unbalanced to teach linear inequalities in one variable. Glue a helium balloon to one side to get negative numbers. Bright third graders get this.
12:30 AM, April 10, 2013
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