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In a certain high school, 80 percent of the seniors are taking calculu https://gmatclub.com/forum/inacertainhighschool80percentoftheseniorsaretakingcalculu321716.html 
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Author:  gmatt1476 [ 20 Apr 2020, 10:55 ] 
Post subject:  In a certain high school, 80 percent of the seniors are taking calculu 
In a certain high school, 80 percent of the seniors are taking calculus, and 60 percent of the seniors who are taking calculus are also taking physics. If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics? (A) 40% (B) 42% (C) 48% (D) 58% (E) 80% PS21260.02 
Author:  ScottTargetTestPrep [ 13 May 2020, 06:21 ] 
Post subject:  Re: In a certain high school, 80 percent of the seniors are taking calculu 
gmatt1476 wrote: In a certain high school, 80 percent of the seniors are taking calculus, and 60 percent of the seniors who are taking calculus are also taking physics. If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics? (A) 40% (B) 42% (C) 48% (D) 58% (E) 80% We can create the equation: Total = Calculus + Physics  Both + Neither 100 = 80 + P  0.6(80) + 10 10 = P  48 58 = P Answer: D 
Author:  nick1816 [ 20 Apr 2020, 11:12 ]  
Post subject:  Re: In a certain high school, 80 percent of the seniors are taking calculu  
Percentage of the seniors that are taking calculus or physics = 10010 = 90% Percentage of the seniors that are taking calculus = 80% Percentage of the seniors that are taking both calculus and physics = 80*0.6 = 48% percent of the seniors that are taking physics = (9080)+48= 58% gmatt1476 wrote: In a certain high school, 80 percent of the seniors are taking calculus, and 60 percent of the seniors who are taking calculus are also taking physics. If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics?
(A) 40% (B) 42% (C) 48% (D) 58% (E) 80% PS21260.02

Author:  Archit3110 [ 21 Apr 2020, 09:02 ] 
Post subject:  Re: In a certain high school, 80 percent of the seniors are taking calculu 
gmatt1476 wrote: In a certain high school, 80 percent of the seniors are taking calculus, and 60 percent of the seniors who are taking calculus are also taking physics. If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics? (A) 40% (B) 42% (C) 48% (D) 58% (E) 80% PS21260.02 solved using 2x2 matrix Calculusno calculustotal Physics481058 no physics321042 total8020100 OPTION D 
Author:  rahulbhusan [ 22 Apr 2020, 06:09 ] 
Post subject:  In a certain high school, 80 percent of the seniors are taking calculu 
gmatt1476 wrote: In a certain high school, 80 percent of the seniors are taking calculus, and 60 percent of the seniors who are taking calculus are also taking physics. If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics? (A) 40% (B) 42% (C) 48% (D) 58% (E) 80% PS21260.02 2X2 Matrix Consider total seniors as 100S Calculus No Calculus Total Physics48S10S58S No Physics32S10S42S Total80S 20S 100S 80% takes calculus, so 80S (Calculus) and 20S (No Calculus) 60% of those who take calculus also takes physics so, 60% of 80S= 48S, takes both calculus and physics. Therefore, 32S takes only calculus and no physics. 10% takes neither, so 10S for no physics and no calculus. Therefore, total physics = 58 S physics%= 58S/100S => 58% ( Option D) Edited the alignments 
Author:  BrentGMATPrepNow [ 28 Apr 2020, 09:08 ] 
Post subject:  Re: In a certain high school, 80 percent of the seniors are taking calculu 
gmatt1476 wrote: In a certain high school, 80 percent of the seniors are taking calculus, and 60 percent of the seniors who are taking calculus are also taking physics. If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics? (A) 40% (B) 42% (C) 48% (D) 58% (E) 80% PS21260.02 One approach is to use the Double Matrix Method. This technique can be used for questions featuring a population in which each member has two characteristics associated with it (aka overlapping sets questions). Here, we have a population of seniors, and the two characteristics are:  taking calculus or not taking calculus  taking physics or not taking physics Since we are asked to find a certain PERCENT, let's say that there are 100 seniors in the school. Our initial diagram looks like this: 80 percent of the seniors are taking calculus So 80 seniors are taking calculus, and the remaining 20 seniors are not taking calculus. We get: 60 percent of the seniors who are taking calculus are also taking physics. We know that 80 seniors are taking calculus 60 percent of 80 = 48 So, 48 seniors are taking calculus AND physics. We get: If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics? 10% of 100 = 10 So 10 seniors are taking NEITHER calculus NOT physics. We get: What percent of the seniors are taking physics? When we complete the rest of the diagram we get: We can now see that 58 of the 100 seniors are taking physics. In other words, 58% of the seniors are taking physics Answer: D Aside: We can also use Venn diagrams and formulae to solve overlapping sets questions. However, as difficulty levels increase, it becomes harder to apply those other approaches, whereas the Double Matrix Method works every time. This question type is VERY COMMON on the GMAT, so be sure to master the technique. To learn more about the Double Matrix Method, watch this video: Then you can try answering the following practice question: 
Author:  CrackverbalGMAT [ 11 Feb 2021, 23:36 ] 
Post subject:  Re: In a certain high school, 80 percent of the seniors are taking calculu 
SOLUTION : A NEW OG 2021 QUESTION Its a question testing on your application skills in Overlapping sets(ConceptSet Theory). Seniors taking Calculus (C)= 80% = 80 students Seniors taking BOTH Calculus and Physics( C AND P) = 60% of 80 =48 students =>Thus, seniors taking ONLY Calculus = 80 48 =32 Seniors taking neither calculus nor physics= 10% = 10 students We know Total = Only C + (C & P) + Only P +Neither => 100 = 32 + 48+ Only P + 10 => 100 = 32+ 48 + Only P + 10 => Only P = 10090 = 10 The total number of seniors taking Physics = Only P + (C & P) =10 + 48 =58 (OPTION D) Hope this helps Devmitra Sen(Math) 
Author:  GMATinsight [ 17 Apr 2021, 00:41 ] 
Post subject:  Re: In a certain high school, 80 percent of the seniors are taking calculu 
gmatt1476 wrote: In a certain high school, 80 percent of the seniors are taking calculus, and 60 percent of the seniors who are taking calculus are also taking physics. If 10 percent of the seniors are taking neither calculus nor physics, what percent of the seniors are taking physics? (A) 40% (B) 42% (C) 48% (D) 58% (E) 80% PS21260.02 Answer: Option D Video solution by GMATinsight Get TOPICWISE: Concept Videos  Practice Qns 100+  Official Qns 50+  100% Video solution CLICK HERE. Two MUST join YouTube channels : GMATinsight (1000+ FREE Videos) and GMATclub 
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Post subject:  Re: In a certain high school, 80 percent of the seniors are taking calculu 
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