Which Ball is Heavier? 9 balls look identically the same but 1 is heavier than the rest balance...
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Which Ball is Heavier? 9 balls look identically the same but 1 is heavier than the rest balance scale How to find the heavier one by weighing 2 times only?
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Transcript of Which Ball is Heavier? 9 balls look identically the same but 1 is heavier than the rest balance...
Which Ball is Heavier?
9 balls look identically the samebut 1 is heavier than the rest
balance scale
How to find the heavier one by weighing 2 times
only?
Hint
balance scale
Weigh once if there are only 3 balls?
3 Balls
balance scale
A B C
3 Cases:1.A heavier than B2.B heavier than A3.same weight
C is heavier
9 Balls
balance scale
3 Cases:1.Group A heavier than group B
Repeat previous step with group A
2.Group B heavier than group A Repeat with group B
3.same weight Repeat with group C
A B C
3 a group
Generalisation
balance scale
More balls?27 balls?81 balls?In general?
27 balls