There are 4 wrenches just unpacked from a box. They all look the same. There might be one defective item which is either heavier or lighter. Fortunately there is a fifth one that is standard. If you can use a scale to weigh only 2 times, can you find out:

1. Is there a defective wrench?

2. If there is a defective item, is it heavier or lighter?

(In reply to re(2): Balanced solution by Bob)

In that case, your solution seems to be okay for both the questions.

Posted by Arunava Dutta on 2004-07-02 11:00:30