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100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote ## In a certain pond, 50 fish were caught, tagged, and returned ##### This topic has 3 expert replies and 0 member replies ### Top Member ## In a certain pond, 50 fish were caught, tagged, and returned ## Timer 00:00 ## Your Answer A B C D E ## Global Stats Difficult In a certain pond, 50 fish were caught, tagged, and returned to the pond. A few days later, 50 fish were caught again, of which 2 were found to have been tagged. If the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond, what is the approximate number of fish in the pond? (A) 400 (B) 625 (C) 1,250 (D) 2,500 (E) 10,000 OA C Source: Official Guide ### GMAT/MBA Expert GMAT Instructor Joined 25 Apr 2015 Posted: 2006 messages Followed by: 14 members Upvotes: 43 Top Reply BTGmoderatorDC wrote: In a certain pond, 50 fish were caught, tagged, and returned to the pond. A few days later, 50 fish were caught again, of which 2 were found to have been tagged. If the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond, what is the approximate number of fish in the pond? (A) 400 (B) 625 (C) 1,250 (D) 2,500 (E) 10,000 We are given that 50 fish were caught, tagged, and returned to the pond, and that a few days later, 50 fish were caught again, of which 2 were tagged. Thus, the percentage of tagged fish is 2/50 = 1/25 = 4%. Since the the percentage of tagged fish in the second catch approximates the percentage of tagged fish in the pond, the approximate number of fish in the pond is: 0.04(total fish) = 50 total fish = 50/0.04 = 5000/4 = 1250 Answer: C _________________ Scott Woodbury-Stewart Founder and CEO ### GMAT/MBA Expert GMAT Instructor Joined 08 Dec 2008 Posted: 12649 messages Followed by: 1245 members Upvotes: 5254 GMAT Score: 770 Top Reply BTGmoderatorDC wrote: In a certain pond, 50 fish were caught, tagged, and returned to the pond. A few days later, 50 fish were caught again, of which 2 were found to have been tagged. If the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond, what is the approximate number of fish in the pond? (A) 400 (B) 625 (C) 1,250 (D) 2,500 (E) 10,000 We can use equivalent ratios here. We're told that the proportion of tagged fish in the 50-fish SAMPLE is equal to the the proportion of tagged fish in the ENTIRE pond. So, (# tagged fish in SAMPLE)/50 = (total # tagged fish)/(total # of fish in POND) Let x = # of fish in the entire pond. We get: 2/50 = 50/x Cross multiply to get 2x = (50)(50) x = 1250 Answer: C Cheers, Brent _________________ Brent Hanneson – Creator of GMATPrepNow.com Use our video course along with Sign up for our free Question of the Day emails And check out all of our free resources GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMAT’s FREE 60-Day Study Guide and reach your target score in 2 months! ### GMAT/MBA Expert GMAT Instructor Joined 25 May 2010 Posted: 15093 messages Followed by: 1859 members Upvotes: 13060 GMAT Score: 790 BTGmoderatorDC wrote: In a certain pond, 50 fish were caught, tagged, and returned to the pond. A few days later, 50 fish were caught again, of which 2 were found to have been tagged. If the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond, what is the approximate number of fish in the pond? (A) 400 (B) 625 (C) 1,250 (D) 2,500 (E) 10,000 Of the 50 fish caught in the second catch, 2 were tagged: 2/50 = 4/100 = 4%. Since the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond, the total number of tagged fish -- 50 -- must be equal to about 4% of the total number of fish in the pond: 50 = (4/100)x 5000/4 = x 1250 = x. The correct answer is C. _________________ Mitch Hunt Private Tutor for the GMAT and GRE GMATGuruNY@gmail.com If you find one of my posts helpful, please take a moment to click on the "UPVOTE" icon. Available for tutoring in NYC and long-distance. For more information, please email me at GMATGuruNY@gmail.com. Student Review #1 Student Review #2 Student Review #3 Free GMAT Practice Test How can you improve your test score if you don't know your baseline score? Take a free online practice exam. Get started on achieving your dream score today! Sign up now. • Free Practice Test & Review How would you score if you took the GMAT Available with Beat the GMAT members only code • 1 Hour Free BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code • FREE GMAT Exam Know how you'd score today for$0

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