Suppose there are 2 defectives among 5

[shinkansenfan]

suppose there are 2 defectives among 5...

suppose there are 2 defectives among 5, test one at a time until you find the 2nd defective, find:

1.you need at most 3 tests
2.given the 2nd defective found at 3rd test, find the p that you find the 1st defective at 1st test.

Thanks.

 

[Ray Vickson]

suppose there are 2 defectives among 5, test one at a time until you find the 2nd defective, find:

1.you need at most 3 tests
2.given the 2nd defective found at 3rd test, find the p that you find the 1st defective at 1st test.

Thanks.

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RGV