Author 
Message 
TAGS:

Hide Tags

Senior Manager
Joined: 21 Oct 2013
Posts: 420

Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
20 Jul 2014, 02:55
Question Stats:
63% (02:51) correct 37% (03:00) wrong based on 257 sessions
HideShow timer Statistics
Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following? A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X)
Official Answer and Stats are available only to registered users. Register/ Login.




Math Expert
Joined: 02 Sep 2009
Posts: 50004

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
20 Jul 2014, 05:51




Intern
Joined: 14 Feb 2013
Posts: 19

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
20 Jul 2014, 20:30
goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) If Henry eats 50 cones in 50% of time it takes Rachel to eat 100 cones. Then, X = 50 , Y = 100 Rachel eats 4 cones in 10 minutes = Rachel eats 1 cone in 5/2 minutes Rachel eats 100 cones in 250 minutes Since Henry eats 50 cones in 50% of time it takes Rachel to eat 100 cones = 250/2 = 125 minutes Henry eats 50 cones in 125 minutes Henry eats 8 cones in 20 minutes Both options A & D give the answer 20 when values are plugged in Is the question right, or should we change our plugged values if such a situation arises?



Intern
Joined: 14 Feb 2013
Posts: 19

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
20 Jul 2014, 20:35
Bunuel wrote: goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) Let x=y=10. So, Henry eats 10 scones in 10% of the time it takes Rachel to eat 10 scones. This means that Henry eats 10 times as fast as Rachel. Rachel eats 4 scones in 10 minutes > 8 scones in 20 minutes. Henry will take 20/10 = 2 minutes to eat 8 scones. Plug y = 10 into the options to see which one of them gives 2. Only A fits. Answer: A. If Henry eats 50 cones in 50% of time it takes Rachel to eat 100 cones. Then, X = 50 , Y = 100 Rachel eats 4 cones in 10 minutes = Rachel eats 1 cone in 5/2 minutes Rachel eats 100 cones in 250 minutes Since Henry eats 50 cones in 50% of time it takes Rachel to eat 100 cones = 250/2 = 125 minutes Henry eats 50 cones in 125 minutes Henry eats 8 cones in 20 minutes Both options A & D give the answer 20 when values are plugged in I plugged in other values as well, same case. Something wrong with the question?



Math Expert
Joined: 02 Sep 2009
Posts: 50004

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
21 Jul 2014, 11:59
hamzakb wrote: goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) If Henry eats 50 cones in 50% of time it takes Rachel to eat 100 cones. Then, X = 50 , Y = 100 Rachel eats 4 cones in 10 minutes = Rachel eats 1 cone in 5/2 minutes Rachel eats 100 cones in 250 minutes Since Henry eats 50 cones in 50% of time it takes Rachel to eat 100 cones = 250/2 = 125 minutes Henry eats 50 cones in 125 minutes Henry eats 8 cones in 20 minutes Both options A & D give the answer 20 when values are plugged in Is the question right, or should we change our plugged values if such a situation arises? For plugin method it might happen that for some particular number(s) more than one option may give "correct" answer. In this case just pick some other numbers and check again these "correct" options only.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread  All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
What are GMAT Club Tests? Extrahard Quant Tests with Brilliant Analytics



Intern
Joined: 07 Feb 2015
Posts: 46

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
14 Mar 2015, 01:55
Rate at which rachel eats = 4/10 spm(scones per minute)=0.4spm Time taken to eat y scones=T=y/0/.4=2.5y according to the statement, rate at which henry eats scones=x/((x/100)T)=100/2.5y=40/y spm time taken to eat 8 scones= 8/(40/y)=y/5 (A)
_________________
Kudos if it helped you in any way



VP
Joined: 07 Dec 2014
Posts: 1104

Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
Updated on: 28 Nov 2015, 13:29
rachel eats Y scones in 5Y/2 minutes henry eats X scones in (X/100)(5Y/2)=XY/40 minutes henry's rate=X/(XY/40)=40/Y scones per minute henry's time for eating 8 scones=8/(40/Y)=Y/5 minutes
Originally posted by gracie on 14 Nov 2015, 22:29.
Last edited by gracie on 28 Nov 2015, 13:29, edited 1 time in total.



Math Expert
Joined: 02 Aug 2009
Posts: 6961

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
14 Nov 2015, 23:12
goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) Hi, R eats Y scones ,say in Z minutes.. so R will eat 4 cones in 4Z/Y but this is equal to 10 min so 4z/y=10 or Z=5Y/2 thus R will eat 8 in 5Y.. now lets see H.. H eats X scones in X% of time R takes, which is 5Y/2 or X scones in X/100*5Y/2=XY/40.. so H eats 8 scones in 8*XY/40(X)=Y/5 ans A
_________________
1) Absolute modulus : http://gmatclub.com/forum/absolutemodulusabetterunderstanding210849.html#p1622372 2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html 3) effects of arithmetic operations : https://gmatclub.com/forum/effectsofarithmeticoperationsonfractions269413.html
GMAT online Tutor



Senior Manager
Joined: 03 Apr 2013
Posts: 280
Location: India
Concentration: Marketing, Finance
GPA: 3

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
07 May 2017, 05:13
chetan2u wrote: goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) Hi, R eats Y scones ,say in Z minutes.. so R will eat 4 cones in 4Z/Y but this is equal to 10 min so 4z/y=10 or Z=5Y/2 thus R will eat 8 in 5Y.. now lets see H.. H eats X scones in X% of time R takes, which is 5Y/2 or X scones in X/100*5Y/2=XY/40.. so H eats 8 scones in 8*XY/40(X)=Y/5 ans A Hi chetan2uIs there a problem with the wording? I didn't get a clue how the answers have come, because the wording is kind of weird for me.
_________________
Spread some love..Like = +1 Kudos



Math Expert
Joined: 02 Aug 2009
Posts: 6961

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
07 May 2017, 06:39
ShashankDave wrote: chetan2u wrote: goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) Hi, R eats Y scones ,say in Z minutes.. so R will eat 4 cones in 4Z/Y but this is equal to 10 min so 4z/y=10 or Z=5Y/2 thus R will eat 8 in 5Y.. now lets see H.. H eats X scones in X% of time R takes, which is 5Y/2 or X scones in X/100*5Y/2=XY/40.. so H eats 8 scones in 8*XY/40(X)=Y/5 ans A Hi chetan2uIs there a problem with the wording? I didn't get a clue how the answers have come, because the wording is kind of weird for me. Hi, The wording is fine but complicated which would be very rare in actuals. You can actually combine first two sentences to get, Henry eats x scones in x%of 10 minutes in which Rachel eats 4 scones. In how much time will Henry eat 8 scones. And if you combine further and want to remove x too.. Henry eats 1 scones in 1% of 10 minutes in which Rachel eats 4 scones. In how much time will Henry eat 8 scones. Now answer is straight ... Henry will eat 8 in 8% of 10 minutes, so \(\frac{8}{100}*10=\frac{8}{10}\) or 4/5 minutes... Now y here is 4, substitute and straight A is the answer..
_________________
1) Absolute modulus : http://gmatclub.com/forum/absolutemodulusabetterunderstanding210849.html#p1622372 2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html 3) effects of arithmetic operations : https://gmatclub.com/forum/effectsofarithmeticoperationsonfractions269413.html
GMAT online Tutor



Intern
Joined: 16 Apr 2015
Posts: 8

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
09 May 2017, 10:12
This is a fairly simple problem if one views in terms of unitary method. Rachel: 4 cones in 10 mins 1 cone in 10/4 mins Y cones in (10/4)Y mins
Henery: Eats X cones in X% of (Time taken by Rachel to eat Y cones) Eats 8 cones in 8% of ((10*Y)/4) = Y/5 OA: A



Senior Manager
Joined: 14 Oct 2015
Posts: 250
GPA: 3.57

Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
Updated on: 15 Jan 2018, 23:23
goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) We know that \(Rate * Time = Work\)  1 Consequently \(Time = \frac{Work}{Rate}\)  2 and \(Rate = \frac{Work}{Time}\)  3 For Rachel \(Work = Y\) \(Time = T\) \(Rate = \frac{Y}{T} = \frac{4}{10} = 0.4\) so Time T for Rachel becomes, \(\frac{Y}{0.4}\) .. using  2 For Henry, \(Time = \frac{T*X}{100}\) \(Work = X\) \(Rate = \frac{Work}{Time} = \frac{X}{T*X/100} = 100/T\) Now using  2 \(Time = \frac{X}{100/T} = \frac{TX}{100}\) Replacing Rachel's Time of \(\frac{Y}{0.4}\) and Henry's 8 scones as \(X\), we get. \(Time = \frac{Y*8}{100*0.4} = \frac{8Y}{40} = \frac{Y}{5}\)
_________________
Please hit Kudos if this post helped you inch closer to your GMAT goal. Procrastination is the termite constantly trying to eat your GMAT tree from the inside. There is one fix to every problem, working harder!
Originally posted by jedit on 15 Jan 2018, 20:12.
Last edited by jedit on 15 Jan 2018, 23:23, edited 1 time in total.



Intern
Joined: 31 Dec 2017
Posts: 28
Concentration: Finance

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
15 Jan 2018, 23:22
Rachel eats 4 scones in 10 mins, so time taken to eat a scone = 10/4 mins.
Time taken by Rachel to eat Y scones = 10Y/4 mins.
Time taken by Henry to eat 8 scones = 8%(10Y/4) mins = 80Y/400 = Y/5 mins. Ans  A.



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 3896
Location: United States (CA)

Re: Henry eats X scones in X percent of the time it takes Rachel
[#permalink]
Show Tags
18 Jan 2018, 14:26
goodyear2013 wrote: Henry eats X scones in X percent of the time it takes Rachel to eat Y scones. If Rachel eats four scones in ten minutes, then the number of minutes it takes Henry to eat 8 scones must be equal to which of the following?
A. Y/5 B. 320/Y C. 100Y/(5X) D. XY/250 E. Y/(5X) The rate of Rachel is 4/10 = 2/5. If we let X = 10 and Y = 4, we see that Henry eats 10 scones in 10% of the time it takes Rachel to eat 4 scones. Since Rachel eats 4 scones in 10 minutes and 10% of 10 minutes is 1 minute, that means Henry eats 10 scones in 1 minutes. If we let m = the number of minutes Henry eats 8 scones, we set up the proportion: 10/1 = 8/m 10m = 8 m = 8/10 = 4/5 Thus, Henry eats 8 scones in 4/5 of a minute. However, since Y = 4, Henry eats 8 scones in Y/5 minutes. Answer: A
_________________
Scott WoodburyStewart
Founder and CEO
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions




Re: Henry eats X scones in X percent of the time it takes Rachel &nbs
[#permalink]
18 Jan 2018, 14:26






