Final answer:
To calculate the number of total quadrats, divide the sample plot size by the area of a single quadrat, then divide the total plot size by the area of a single quadrat, resulting in 215 total quadrats used.
Step-by-step explanation:
The question concerns the use of quadrats to measure a sample plot as part of estimating the size and density of a population in an area. In the given scenario, divers measured a total plot of 860 square meters using individual quadrat samples of 60 square meters each, with each quadrat having dimensions of 2 meters by 2 meters. To determine the number of total quadrats used, we must first calculate the area of a single quadrat, which is 2m × 2m = 4 square meters. Then, we divide the sample plot size by the area of a single quadrat to find the number of quadrats: 60 square meters ÷ 4 square meters per quadrat = 15 quadrats. Finally, to find the total number of quadrats used for the entire plot, we divide the total plot size by the area of a single quadrat: 860 square meters ÷ 4 square meters per quadrat = 215 quadrats.