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Twenty metal blocks (Posted on 2005-06-02)

Twenty metal blocks are of the same size and external appearance; some are aluminum, and the rest are duraluminum, which is heavier.

Using a pan balance to determine how many blocks are aluminum, what is the minimum number of weighings to be done?

See The Solution Submitted by pcbouhid

Rating: 3.5000 (2 votes)

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Puzzle Answer

Comment 19 of 19 |

1) On the first trial, one of the pans is heavier.

At least TEN weight trials are required

2) On the first weigh trial the pans balance.

At least 11 weight trials are required.

Edited on March 19, 2024, 3:16 am

Posted by K Sengupta on 2024-03-19 03:15:17

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