I30-35

Question

A wildlife conservation organization is conducting a study on a population of birds. In this study, pairs of birds are tagged and released into designated habitats. Each pair consists of exactly two birds, and no bird is part of more than one pair. The study begins with 1024 birds being tagged and released into the habitats. After each week, half of the pairs of birds in the habitats remain in the study, while the other half are removed from the habitats and returned to a safe environment.
 
Select for  Weeks  the number of weeks since the birds were released into the habitats, and select for  Pairs  the number of pairs of birds still in the habitats after that number of weeks that would be jointly consistent with the given information. Make only two selections, one in each column.

Bunuel · Answer

Official Solution:

The study begins with 1024 birds, which means 1024/2 = 512 pairs.
 
After each week, half of the pairs remain in the habitats:
 
• Week 1: 512/2 = 256 pairs
 
• Week 2: 256/2 = 128 pairs
 
• Week 3: 128/2 = 64 pairs
 
• Week 4: 64/2 = 32 pairs
 
• Week 5: 32/2 = 16 pairs
 
• Week 6: 16/2 = 8 pairs
 
...
 
We need to look for the number of weeks and the corresponding number of pairs from this list that are present in the options.
 
We have 6 weeks and 8 pairs — both values are in the options.

Correct answer:

Weeks  "6"

Pairs  "8"

Apoorv0194 · Answer

I did not quite understand the solution. Week 1 will have 512 in habitat and 512 released right ??

Bunuel · Answer

No. At the start, 512  pairs  are released into habitats. After 1 week, half (256) remain, and the other 256 are removed.

Apoorv0194 · Answer

Thanks, Understood. Missed out on the word "Pairs"

I30-35

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