Number of birds that did not lay eggs = Total number of birds - Number of eggs laid
Given information:
Total number of birds = 2,000
Number of eggs laid = 1,680 per day
Number of birds that did not lay eggs = 2,000 - 1,680 = 320
Now, we can calculate the percentage of birds that did not lay eggs:
Percentage of birds that did not lay eggs = (Number of birds that did not lay eggs / Total number of birds) x 100
Percentage of birds that did not lay eggs = (320 / 2,000) x 100 = 0.16 x 100 = 16%
Therefore, the percentage of birds that did not lay eggs on that particular day is 16%.