A grassland of 2000 m² is sampled with twenty 1 m² quadrats, which contain 60 plants of one species in total. What is the best estimate of the population in the whole field?
Answer and explanation
Correct answer: D. 6000
- Step 1: Mean per quadrat = 60 ÷ 20 = 3 plants per m².
- Step 2: Scale up: 3 × 2000 = 6000.
Answer
6000.
Why not the others: 3: this is the mean per m². 120 000: the total count was multiplied by 2000 instead of the mean. 60: this is the total counted.
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