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A fresh tricky TA dataset on weighted average [#permalink]
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Try this tricky question fresh from the eGMAT bakery! The data given below for 15 movies on their performance on 3 attributes Performance, Entertainment, and Script. Each attribute is awarded marks out of 10 by a select group, out of which Total Score Point is calculated. For each of the following statements, select ‘Yes’ if statement is true based solely on the information provided in the table; otherwise select ‘No’.1. In the calculation of Total Score Points, equal weightage was given to both Performance Score Points and Script Score Points. 2. If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. 3. If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease.I have attached an excel file of this table. Please make sure that you only use sorting feature of Excel, that too in ascending order only. Want to view similar table analysis questions with interactive audio visual soltion? Register here at eGMATShalabh Jain
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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23 Jan 2013, 05:49
egmat wrote: Try this tricky question fresh from the eGMAT bakery! The data given below for 15 movies on their performance on 3 attributes Performance, Entertainment, and Script. Each attribute is awarded marks out of 10 by a select group, out of which Total Score Point is calculated. For each of the following statements, select ‘Yes’ if statement is true based solely on the information provided in the table; otherwise select ‘No’.In the calculation of Total Score Points, equal weightage was given to both Performance Score Points and Script Score Points. 2. If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. 3. If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease.Shalabh Jain Nice Question This question tests the fundamentals of Weighted Average concept Answer 1  If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase Yes Original weights are 80% (for Performance & Script combined) & 20% for Entertainment. New weights are 60% (for Performance & Script combined) & 40% for Entertainment. Answer 2 If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease NoHi Shalabh, Do you really think Question1 is a good representative of GMAT IR because I think part1 is based on the fundamentals of TwoPart Question. Regards, Fame
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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23 Jan 2013, 08:19
fameatop wrote: egmat wrote: Try this tricky question fresh from the eGMAT bakery! The data given below for 15 movies on their performance on 3 attributes Performance, Entertainment, and Script. Each attribute is awarded marks out of 10 by a select group, out of which Total Score Point is calculated. For each of the following statements, select ‘Yes’ if statement is true based solely on the information provided in the table; otherwise select ‘No’.In the calculation of Total Score Points, equal weightage was given to both Performance Score Points and Script Score Points. 2. If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. 3. If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease.Shalabh Jain Nice Question This question tests the fundamentals of Weighted Average concept Answer 1  If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase Yes Original weights are 80% (for Performance & Script combined) & 20% for Entertainment. New weights are 60% (for Performance & Script combined) & 40% for Entertainment. Answer 2 If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease NoHi Shalabh, Do you really think Question1 is a good representative of GMAT IR because I think part1 is based on the fundamentals of TwoPart Question. Regards, Fame Hi Fame, Thank you for complement. Well your answers to all 3 parts are correct. Let me first put down the correct answers. Q1 , Q2 , & Q3 Now, to answer your query, I request you to kindly refer OG 13/Q #20 This question is also based on Table Analysis testing weighted average concept. Yes, you are right, this concept can also be tested in 2 part question type. By the way, I will be interested to know How you solved Q2 ? If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. Shalabh
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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23 Jan 2013, 09:04
Hi
can you please clarify how to get answers this question ,i couldn't understand your explanation. please elaoborate
Thanks and regards, Sidd



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Re: A fresh tricky TA dataset on weighted average [#permalink]
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23 Jan 2013, 11:12
how to answer these questions? How to solve it? Please help



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Re: A fresh tricky TA dataset on weighted average [#permalink]
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23 Jan 2013, 23:20
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egmat wrote: fameatop wrote: egmat wrote: Try this tricky question fresh from the eGMAT bakery! The data given below for 15 movies on their performance on 3 attributes Performance, Entertainment, and Script. Each attribute is awarded marks out of 10 by a select group, out of which Total Score Point is calculated. For each of the following statements, select ‘Yes’ if statement is true based solely on the information provided in the table; otherwise select ‘No’.In the calculation of Total Score Points, equal weightage was given to both Performance Score Points and Script Score Points. 2. If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. 3. If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease.Shalabh Jain Nice Question This question tests the fundamentals of Weighted Average concept Answer 1  If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase Yes Original weights are 80% (for Performance & Script combined) & 20% for Entertainment. New weights are 60% (for Performance & Script combined) & 40% for Entertainment. Answer 2 If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease NoHi Shalabh, Do you really think Question1 is a good representative of GMAT IR because I think part1 is based on the fundamentals of TwoPart Question. Regards, Fame Hi Fame, Thank you for complement. Well your answers to all 3 parts are correct. Let me first put down the correct answers. Q1 , Q2 , & Q3 Now, to answer your query, I request you to kindly refer OG 13/Q #20 This question is also based on Table Analysis testing weighted average concept. Yes, you are right, this concept can also be tested in 2 part question type. By the way, I will interested to know How you solved Q2 ? If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. Shalabh Hi Shalabh, 2nd question is the most trickiest one. My shortcut is based simply on the concept of "SeeSaw". Step1 The original weight given to Entertainment has to be 20% (as confirmed in question 1) Step2  Either find out the average of Performance & Script OR Double the Entertainment points (Group1) & add the points of Performance & Script (Group2) Step3 Now compare the values of these two groups  Group 1 Entertainment Group 2 Performance & Script Step4 If the absolute value of Group1 is higher than Group2, then only Total Score points will increase because we are increasing the weights from 20% to 40%. (In any other case, Total score points will either remain constant or decrease) Step5 Count the number of observations  Exactly 9 observations. Hope this concept will help many others to come. Fame
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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24 Jan 2013, 00:20
egmat wrote: fameatop wrote: egmat wrote: Try this tricky question fresh from the eGMAT bakery! The data given below for 15 movies on their performance on 3 attributes Performance, Entertainment, and Script. Each attribute is awarded marks out of 10 by a select group, out of which Total Score Point is calculated. For each of the following statements, select ‘Yes’ if statement is true based solely on the information provided in the table; otherwise select ‘No’.In the calculation of Total Score Points, equal weightage was given to both Performance Score Points and Script Score Points. 2. If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. 3. If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease.Shalabh Jain Nice Question This question tests the fundamentals of Weighted Average concept Answer 1  If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase Yes Original weights are 80% (for Performance & Script combined) & 20% for Entertainment. New weights are 60% (for Performance & Script combined) & 40% for Entertainment. Answer 2 If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease NoHi Shalabh, Do you really think Question1 is a good representative of GMAT IR because I think part1 is based on the fundamentals of TwoPart Question. Regards, Fame Hi Fame, Thank you for complement. Well your answers to all 3 parts are correct. Let me first put down the correct answers. Q1 , Q2 , & Q3 Now, to answer your query, I request you to kindly refer OG 13/Q #20 This question is also based on Table Analysis testing weighted average concept. Yes, you are right, this concept can also be tested in 2 part question type. By the way, I will interested to know How you solved Q2 ? If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. Shalabh Hi Shalabh, 2nd question is the most trickiest one. My shortcut is based simply on the concept of "SeeSaw". Step1 The original weight given to Entertainment has to be 20% (as confirmed in question 1) Step2  Either find out the average of Performance & Script OR Double the Entertainment points (Group1) & add the points of Performance & Script (Group2) Step3 Now compare the values of these two groups  Group 1 Entertainment Group 2 Performance & Script Step4 If the absolute value of Group1 is higher than Group2, then only Total Score points will increase because we are increasing the weights from 20% to 40%. (In any other case, Total score points will either remain constant or decrease) Step5 Count the number of observations  Exactly 9 observations. Hope this concept will help many others to come. Fame[/quote]  Hi Fame, Nice to see step by step approach to answer this question. Yes, it is a tricky question for sure. I provide you another shortcut approach to logically deduce the answer to this question. Pl. see my another post. Shalabh
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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24 Jan 2013, 02:40
egmat wrote: Try this tricky question fresh from the eGMAT bakery! The data given below for 15 movies on their performance on 3 attributes Performance, Entertainment, and Script. Each attribute is awarded marks out of 10 by a select group, out of which Total Score Point is calculated. For each of the following statements, select ‘Yes’ if statement is true based solely on the information provided in the table; otherwise select ‘No’.1. In the calculation of Total Score Points, equal weightage was given to both Performance Score Points and Script Score Points. 2. If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. 3. If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease.I have attached an excel file of this table. Please make sure that you only use sorting feature of Excel, that too in ascending order only. Want to view similar table analysis questions with interactive audio visual soltion? Register here at eGMATShalabh Jain Now is the time to provide solution to this question. Before you look at the solution, I do recommend that you first read my article on weighted average whatyouchooseiswhatyouweigh143895.html. This will make sure, you absorb the concept, and its application better. Question 1 In the calculation of Total Score Points, equal weightage was given to both Performance Score Points and Script Score Points.Understand the question 3 attributes Performance, Entertainment, and Script's score points are primary data, and Total score points is a derived data. It means that Total score points is derived out of a mathematical relationship among Performance, Entertainment, and Script score points. The first part of the question i.e. Q1, states that their relationship is governed by weights, or we can simply infer that Total score points is not a simple average of Performance, Entertainment, and Script score points. Performance, Entertainment, and Script score points might have been mixed in some unknown proportion to derive the value of total score points. Per the first part of question, Is Weight of Performance score points = Weight of Script score points ?Traditional Approach Step 1 Say Total weight = 1. Out of which, weight of Performance score points = weight of Script score points = x, & Weight of Entertainment score points = y. So x+y+x=1 => y=12x. Step 2 Formulate mathematical formula Total score points = x* Performance score points + y* Entertainment score points + x* Script score pointsWe can simplify this by plugging in the value of y as 12x. So the equation becomes Total score points = x*( Performance score points + Script score points )+ (12x)* Entertainment score points. This gives, \(x=[\frac{(Total score points  Entertainment score points)}{( Performance score points + Script score points  2 Entertainment score points)}]\) Step 3 Pick any of the 2 listed movies, and plug in the relevant score points in the equation above. If value of x is same for both the movies, then we an say our assumption of taking weight of Performance score points = weight of Script score points was correct. Say, we take Predator, & Total Recall movies... For Predator, \(x= \frac{(5.744.7)}{(7.4+4.62*4.7)}\) This gives x=0.4. Now, we try with Total Recall, \(x= \frac{(8.728.8)}{(9+8.42*8.8)}\) This also gives x=0.4. This means our assumption of taking weight of Performance score points = weight of Script score points was correct. So the answer is Yes. Well, I do not really recommend this approach, as this approach involves handling 2 variables x, & y. Alternate Approach Step 1 Say weight of Performance score points = weight of Script score points = 1, & weight of Entertainment score points = z. So total weight = 2+z. Step 2 Formulate mathematical formula (2+z)* Total score points = 1* Performance score points + z* Entertainment score points + 1* Script score pointsThis gives, \(z=[\frac{( Performance score points + Entertainment score points  2* Total score points)}{(Total score points Script score points)}]\) Step 3 Pick any of the 2 listed movies, and plug in the relevant score points in the equation above. If value of z is same for both the movies, then we an say our assumption of taking weight of Performance score points = weight of Script score points was correct. Say, we take Predator, & Total Recall movies... For Predator, \(z= \frac{(7.4+4.72*5.74)}{(5.744.6)}\) This gives z=0.5. Now, we try with Total Recall, \(z= \frac{(9+8.82*8.72)}{(8.728.4)}\) This also gives z=0.5. This means our assumption of taking weight of Performance score points = weight of Script score points was correct. So the answer is Yes. This means that Performance, Entertainment, and Script score points are weighted in the ratio of 1:0.5:1 => 2:1:2 => 40%:20%:40% (In terms of %)Question 2 If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. Understand the question Presently, the weightage of Entertainment Score Points is 20% out of 100%. Now it is doubled. It means that it becomes 40% now. Not to accommodate extra 20% (4020), Performance, & Script score points will have to sacrifice 10% each. So the new weighage of 3 attribute would be 30%:40%:30%. Approach Before answering this question, let us look at the concept of weighted average. If you have not visited my weighted article till now, pl. do so now. whatyouchooseiswhatyouweigh143895.htmlSay, there are 3 numbers 10, 12 & 20. Their average would be 14. Now, a one more number 12 is added to it. So we have 4 #. 10, 12, 12 & 20. Now, my question to you is Can you deduce whether the average of 4 # would be less than 14 or more than 14? Weighted Average Fundamental If a new data, whose value is less current average of few data is added, then new average would be less than the current average. Similarly, viseversa true for greater value. Why is so? It is because, the the new data pulls the average towards it. Now, coming to our question If the weightage of Entertainment Score Points is doubled to calculate Total Score Points, then there are exactly 9 movies, whose Total Score Points will increase. We are interested to know, new Total Score Points will increase compared to current Total Score Points or not. So per Weighted Average Fundamental , Entertainment Score Points weightage is doubled, or we can say that a new data is included. We can deduce that for those movies, whose Entertainment Score Points is more than Total Score Points, new Total Score Points will increase. There are exactly 9 movies, whose Entertainment Score Points is more than Total Score Points. these are Lara Croft, Rocky, Rocky 3, Rocky Balboa, Salt, Tango & Cash, Terminator, Total Recall, True Lies. Answer is Yes. Question 3 If for each of the Arnold Swaznegger movies, respective movie Performance Score Point is swapped with Script Score Point, then the Total Score Point of exactly one movie of Arnold Swaznegger will decrease.Understand the question Currently, Performance, Entertainment, and Script score points are weighed in the ratio of 40%:20%:40%. The weights of Performance, and Script score points are equal, hence swapping will have no impact. Answer is N0. Hope this explanation helps. Shalabh Do view comparemeanandmedianinlessthan20seconds146191.html to get something refreshing on mean and median.
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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29 Jan 2013, 00:20
what is weightage average? pls help explain this concept thank you e gmat expert.
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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29 Jan 2013, 03:02
thangvietnam wrote: what is weightage average? pls help explain this concept thank you e gmat expert. Hi, This is an important question. Pl. read this article for you understanding, and solve the questions given as exercise. whatyouchooseiswhatyouweigh143895.htmlAfter reading the article, you can ask me relevant questions. Shalabh
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Re: A fresh tricky TA dataset on weighted average [#permalink]
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16 Jul 2013, 08:28
Hello Shalabh,
Thank you for your help and problems you are putting on this forum. Just one question, are these IR problems that you make harder or easier than official ones. I would say a lot harder but I cannot tell for sure since I am a beginner with IR section.



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Re: A fresh tricky TA dataset on weighted average [#permalink]
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20 Jul 2013, 21:04
only a Calculator will be provided in GMAT and there are no experimental sections
Still
1. Yes , one has to do calculations to figure that out 2. Yes, because the nine movies will all have the Entertainment scores higher than both perf and script 3. No, because Performance and Script have the same weight, so there would be no difference



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Re: A fresh tricky TA dataset on weighted average [#permalink]
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04 Aug 2013, 10:55
thanks so much for the post, however if the weightage is modified from 40:20:40 to 30%:40%:30%, wont the decrease in performance and script scores affect the total score and not just the entertainment score points from 20 >40?




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