When the KJ Reservoir (KJR) was built, a single, well-known species of fish was introduced for its role in the new ecosystem. KJR is a popular destination for a public fishing season that extends from June through August each year. Each May 1, the area’s wildlife management team generates an estimate of the number of these fish in the reservoir. The team has determined that the fish’s population should be no less than 1,500 fish at the start of the fishing season—less than 1,500, and the team acquires and releases enough fish to make up the difference. The fish of this species reproduce once a year in mid-September. Due to environmental factors, of the species’s total population at the end of September, 80% will survive until the following May. It is estimated that KJR cannot support a healthy, reproductive fish population greater than 2,000.To estimate the total number of individuals of an animal species in a particular area, some researchers use the following method: The researchers first capture a number (M) of individual animals of the species (the capture group) without doing harm. Each is marked, released, and allowed to disperse back into its general population. A number (N) of individual animals are then captured in a second group (the recapture group), some of which will have been captured in both groups, provided both the capture group and recapture group are sufficiently large. Researchers then use the equation below to estimate P, which represents the total number of animals in the area: number of fish common to both groups/N = \frac{M}{P}To predict the annual increase in fish population in KJR due to reproduction, the wildlife management team uses the following model developed from past population data from KJR. The model expresses population increase in terms of the fish population at the start of September (P) the maximum supported healthy fish population (C), and a constant chosen to fit the model to the data (r) https://gmatclub.com/forum/download/file.php?id=55657 On May 1 last year, KJR’s wildlife management team marked the 60 fish comprising the capture group. The recapture group had 100 fish, including exactly 5 from the capture group. 123.jpg

Official Explanation 1. Based on the information provided, which one of the following was the team’s estimate of KJR’s fish population? To find the team’s estimate of the fish population, insert the given data into the equation provided in the second tab, where M is the number of fish in the capture group (60), N is the number of fish in the recapture group (100), 5 fish are common to both groups, and P is the estimated fish population: 5/100=60/P. Cross-multiply to get 5P = 6,000. Divide both sides of the equation by 5 to get P = 1,200. The correct answer is 1,200. 2. For each of the following scenarios, select Restock if the scenario would indicate that the team will need to restock the reservoir. Otherwise, select Do not restock. Insert the given data into the equation provided, where M is the number of fish in the capture group (60), N is the number of fish in the recapture group (60), and P is the total fish population: (number of fish common to both groups)/(P)=60/P. Cross-multiplying gives P(number of fish common to both groups)= 3,600. Isolating P gives P=3600/(number of fish common to both groups). If P is less than 1,500, the information in the discussion indicates that the team will need to restock the lake. RO1 From the analysis above, P=3,600/2= 1,800. This number is not less than 1,500, so the team will not need to restock the lake. The correct answer is Do not restock. RO2 From the analysis above, P=3,600/4=900. This number is less than 1,500, so the team will need to restock the lake. The correct answer is Restock. RO3 From the analysis above, P=3,600/6=600. This number is less than 1,500, so the team will need to restock the lake. The correct answer is Restock. 3. Assume that at the beginning of next year’s fishing season the fish population will be at the minimum level for the start of the fishing season. For each of the following numbers of fish removed from KJR during that fishing season, select Yes if the model for population increase predicts that the fish population will increase by at least 40 fish due to reproduction. Otherwise, select No. The Discussion indicates that the fish’s population should be no less than 1,500 at the start of the fishing season. Therefore, at the end of that season (the start of September), the population P will be 1,500 minus the number of fish removed during the season. With this number, the graph provided can then be used to predict the increase in the fish population due to reproduction. RO1 P=1,500−100=1,400. According to the graph, a P of 1,400 is predicted to increase by slightly more than 40 fish. The correct answer is Yes. RO2 P=1,500−200=1,300. According to the graph, a P of 1,300 is predicted to increase by approximately 45 fish. The correct answer is Yes. RO3 P=1,500−600=900. According to the graph, a P of 900 is predicted to increase by approximately 50 fish. The correct answer is Yes.

1)B,Since we will use the formula: number of fish common to both groups/N =M/P Here per the data mentioned in table 3: Common fish =5 ,N(recapture fish)=100, M(capture fish)=60 5/100 = 60/P P= 1200(Fish population) 2)Now here for this scenario Capture fish=60, Recapture fish=60,And if we go by total population as 1200, so common fish can be = Common fish/60= 60/1200 ,so common fish =3 So for the above mentioned cases : For 4 & 6 we need to restock the reservoir and for 2 common fish we do not need to restock since the available common fish qouta is 3 3)So if we consider the minimum population at the start of season then that would be 1500(because below than that requires refilling from the team) ,now if we see the graph in third table we see that if remove: 1)100 fish removed --- 1400 fish remain ,so per the graph the increment would be of 40 fish----statement - Yes 2)200 fish removed---- 1300 fish remain,so per the graph the increment would be roughly of 45 fish ---- statement -Yes 3)600 fish removed---- 900 fish remain per the graph the increment would be roughly of 48 fish ---- statement -Yes Posted from my mobile device

A silly mistake I committed: I mistook graph's Y axis to be population rather than population increase.

Bunuel Q1 is incomplete. Please add THE FOLLOWING DATA TO THE QUESTION: "On May 1 last year, KJR's wildlife management team marked the 60 fish comprising the capture group. The recapture group had 100 fish, including exactly 5 from the capture group."

Can you please provide a screenshot? That would help greatly. Thank you!

When the KJ Reservoir (KJR) was built, a single, well-known species of : Multi-Source Reasoning (MSR)

Restock	Do not restock
		Exactly 2 fish were in both the capture and recapture groups.
		Exactly 4 fish were in both the capture and recapture groups.
		Exactly 6 fish were in both the capture and recapture groups.

When the KJ Reservoir (KJR) was built, a single, well-known species of

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