Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 48074

Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
29 Apr 2015, 04:10
Question Stats:
58% (02:17) correct 42% (02:31) wrong based on 107 sessions
HideShow timer Statistics




Retired Moderator
Joined: 06 Jul 2014
Posts: 1247
Location: Ukraine
Concentration: Entrepreneurship, Technology
GMAT 1: 660 Q48 V33 GMAT 2: 740 Q50 V40

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
29 Apr 2015, 06:10
Bunuel wrote: Different breeds of dogs get older at different rates in “dog years.” Livonian wolfhounds age 7 times as fast as humans, whereas Khazarian terriers age 5 times as fast and Akkadian retrievers age 4 times as fast. If Dan bought a newborn Akkadian on January 1, 2010, a newborn Khazarian 1 year later, and a newborn Livonian 1 year after that, in what year will the sum of the dogyear ages of the Akkadian and the Khazarian first be exceeded by twice the age of the Livonian in dog years, rounding all ages down to the nearest integer?
A. 2013 B. 2014 C. 2015 D. 2016 E. 2017
Kudos for a correct solution. Let's \(x\) denotes number of years. Then \(L = 7*(x2)\); \(K = 5*(x1)\) and \(A = 4x\) And we need to find \(x\) when \(K+A<2L\) \(5*(x1) + 4x < 2*(7*(x2))\) \(5x  5 + 4x < 14x28\) \(23 < 5x\) Ans as we know \(x\) is integer so \(x\) should be \(5\) \(2010+5 = 2015\) Answer is C
_________________
Simple way to always control time during the quant part. How to solve main idea questions without full understanding of RC. 660 (Q48, V33)  unpleasant surprise 740 (Q50, V40, IR3)  antidebrief




BSchool Forum Moderator
Joined: 10 Jan 2013
Posts: 295
Location: India
Concentration: Marketing, Entrepreneurship
GMAT 1: 690 Q47 V39 GMAT 2: 710 Q47 V41 GMAT 3: 720 Q50 V38
WE: Marketing (Retail)

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
29 Apr 2015, 07:02
You can solve it by making a table using the values given in the question. The year when 2L exceeds Sum of A & K is 2015 Hence  C
Attachments
Screen Shot 20150429 at 7.30.29 pm.png [ 26.17 KiB  Viewed 1764 times ]



Manager
Joined: 15 Mar 2015
Posts: 113

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
29 Apr 2015, 09:22
I'm going with C: I made a chart starting at 2012: A+K=13 L=0. Then I added 9 to a+k for each year and 14 to L for each year. 2013:AK=22 L=14 2014:AK=31 L=28 2015:AK=40 L=42 thus, 2015 is the correct answer. => C
_________________
I love being wrong. An incorrect answer offers an extraordinary opportunity to improve.



Senior Manager
Joined: 28 Feb 2014
Posts: 295
Location: United States
Concentration: Strategy, General Management

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
29 Apr 2015, 16:52
Livonian wolfhounds age 7 times as fast as humans: 7h Khazarian terriers age 5 times as fast: 5h Akkadian retrievers age 4 times as fast: 4h
Only in year 2015 does Akkadian + Khazarian be less than twice the age of a Livonian 20+20 < 2*21 40<42
Answer: C



Senior Manager
Joined: 21 Jan 2015
Posts: 345
Location: India
Concentration: Strategy, Marketing
GMAT 1: 620 Q48 V28 GMAT 2: 690 Q49 V35
WE: Sales (Consumer Products)

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 00:01
Bunuel wrote: Different breeds of dogs get older at different rates in “dog years.” Livonian wolfhounds age 7 times as fast as humans, whereas Khazarian terriers age 5 times as fast and Akkadian retrievers age 4 times as fast. If Dan bought a newborn Akkadian on January 1, 2010, a newborn Khazarian 1 year later, and a newborn Livonian 1 year after that, in what year will the sum of the dogyear ages of the Akkadian and the Khazarian first be exceeded by twice the age of the Livonian in dog years, rounding all ages down to the nearest integer?
A. 2013 B. 2014 C. 2015 D. 2016 E. 2017
Ans: C in one year A will age 4 years, K will age 5 years, L will age 7 years sol: A+k 2L  2013 22 14 2014 31 28 2015 40 42 2015 is the answer
_________________
 The Mind is Everything, What we Think we Become. Kudos will encourage many others, like me. Please Give Kudos !! Thanks



Manager
Joined: 15 Mar 2015
Posts: 113

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 06:00
After reconsideration, wouldn't the actual event where 2L=K+A come during 2014? At the beginning of 2015 we know that 2L>K+A, so therefore the event should have happened at 2014.
_________________
I love being wrong. An incorrect answer offers an extraordinary opportunity to improve.



Retired Moderator
Joined: 06 Jul 2014
Posts: 1247
Location: Ukraine
Concentration: Entrepreneurship, Technology
GMAT 1: 660 Q48 V33 GMAT 2: 740 Q50 V40

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 07:07
MarkusKarl wrote: After reconsideration, wouldn't the actual event where 2L=K+A come during 2014? At the beginning of 2015 we know that 2L>K+A, so therefore the event should have happened at 2014. All events occur at 1 January. So technically it's 2015 year.
_________________
Simple way to always control time during the quant part. How to solve main idea questions without full understanding of RC. 660 (Q48, V33)  unpleasant surprise 740 (Q50, V40, IR3)  antidebrief



Manager
Joined: 15 Mar 2015
Posts: 113

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 07:58
Harley1980 wrote: MarkusKarl wrote: After reconsideration, wouldn't the actual event where 2L=K+A come during 2014? At the beginning of 2015 we know that 2L>K+A, so therefore the event should have happened at 2014. All events occur at 1 January. So technically it's 2015 year. At January 1st 2015, 2L=42 and K+A=40, as such 2L has been more than K+A prior to January 1st 2015. What am I missing?
_________________
I love being wrong. An incorrect answer offers an extraordinary opportunity to improve.



Retired Moderator
Joined: 06 Jul 2014
Posts: 1247
Location: Ukraine
Concentration: Entrepreneurship, Technology
GMAT 1: 660 Q48 V33 GMAT 2: 740 Q50 V40

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 08:08
MarkusKarl wrote: Harley1980 wrote: MarkusKarl wrote: After reconsideration, wouldn't the actual event where 2L=K+A come during 2014? At the beginning of 2015 we know that 2L>K+A, so therefore the event should have happened at 2014. All events occur at 1 January. So technically it's 2015 year. At January 1st 2015, 2L=42 and K+A=40, as such 2L has been more than K+A prior to January 1st 2015. What am I missing? 31 december 2014, 2L=28 and K+A=31 1st January day of birthday all dogs At January 1st 2015, 2L=42 and K+A=40 So only at 1 January 2L became bigger than K+A
_________________
Simple way to always control time during the quant part. How to solve main idea questions without full understanding of RC. 660 (Q48, V33)  unpleasant surprise 740 (Q50, V40, IR3)  antidebrief



Manager
Joined: 15 Mar 2015
Posts: 113

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 08:20
Harley1980 wrote: 31 december 2014, 2L=28 and K+A=31
1st January day of birthday all dogs At January 1st 2015, 2L=42 and K+A=40
So only at 1 January 2L became bigger than K+A
This would mean that the dogs age only once a year and that time is discreet, not continuous. How am I to interpret the question to get this definition?
_________________
I love being wrong. An incorrect answer offers an extraordinary opportunity to improve.



Manager
Joined: 15 Mar 2015
Posts: 113

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 08:22
Wouldn't L be 364/365*7+14 at the next to last day of 2014? (just to clarify how I interpret the continuous flow of age)
_________________
I love being wrong. An incorrect answer offers an extraordinary opportunity to improve.



Retired Moderator
Joined: 06 Jul 2014
Posts: 1247
Location: Ukraine
Concentration: Entrepreneurship, Technology
GMAT 1: 660 Q48 V33 GMAT 2: 740 Q50 V40

Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 08:49
MarkusKarl wrote: Wouldn't L be 364/365*7+14 at the next to last day of 2014? (just to clarify how I interpret the continuous flow of age) I'm not sure, but I think it's common rule. For example when some shop make age restrictions on alcohol sale. They do not use continuous flow of age. There is two possible variants: you are 21 and you can bye product or you fewer than 21 and you can't bye this product. And it doesn't matter that today you are 20 and tomorrow will be 21.
_________________
Simple way to always control time during the quant part. How to solve main idea questions without full understanding of RC. 660 (Q48, V33)  unpleasant surprise 740 (Q50, V40, IR3)  antidebrief



Manager
Joined: 15 Mar 2015
Posts: 113

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 09:07
Harley1980 wrote: MarkusKarl wrote: Wouldn't L be 364/365*7+14 at the next to last day of 2014? (just to clarify how I interpret the continuous flow of age) I'm not sure, but I think it's common rule. For example when some shop make age restrictions on alcohol sale. They do not use continuous flow of age. There is two possible variants: you are 21 and you can bye product or you fewer than 21 and you can't bye this product. And it doesn't matter that today you are 20 and tomorrow will be 21. I get your point, but I don't think that this is really addressing my concern. I will simply hope that the GMAT will not include such a question when I do my test.
_________________
I love being wrong. An incorrect answer offers an extraordinary opportunity to improve.



Senior Manager
Joined: 21 Jan 2015
Posts: 345
Location: India
Concentration: Strategy, Marketing
GMAT 1: 620 Q48 V28 GMAT 2: 690 Q49 V35
WE: Sales (Consumer Products)

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
30 Apr 2015, 17:08
MarkusKarl wrote: Harley1980 wrote: MarkusKarl wrote: Wouldn't L be 364/365*7+14 at the next to last day of 2014? (just to clarify how I interpret the continuous flow of age) I'm not sure, but I think it's common rule. For example when some shop make age restrictions on alcohol sale. They do not use continuous flow of age. There is two possible variants: you are 21 and you can bye product or you fewer than 21 and you can't bye this product. And it doesn't matter that today you are 20 and tomorrow will be 21. I get your point, but I don't think that this is really addressing my concern. I will simply hope that the GMAT will not include such a question when I do my test. My take on this is "question says rounding all age down to there nearest integer value, so I rounded the age of Humans also, because it is also included in the question and we are comparing all ages in terms of X*human age. 2014,2015,2016 are the rounded age calculation points.
_________________
 The Mind is Everything, What we Think we Become. Kudos will encourage many others, like me. Please Give Kudos !! Thanks



Manager
Joined: 15 Mar 2015
Posts: 113

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
01 May 2015, 00:48
dkumar2012 wrote: My take on this is "question says rounding all age down to there nearest integer value, so I rounded the age of Humans also, because it is also included in the question and we are comparing all ages in terms of X*human age. 2014,2015,2016 are the rounded age calculation points.
I interpreted that part differently than you as well. That's what actually made me want to pick 2014 after reconsidering. I decided to round all ages at the end, and then I was at the end of the year 2014, rounding 2014 down instead of up it would yield 2014 as the answer. But I'm dropping this now, I am afraid I am confusing people even more with this discussion.
_________________
I love being wrong. An incorrect answer offers an extraordinary opportunity to improve.



Math Expert
Joined: 02 Sep 2009
Posts: 48074

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
04 May 2015, 04:13
Bunuel wrote: Different breeds of dogs get older at different rates in “dog years.” Livonian wolfhounds age 7 times as fast as humans, whereas Khazarian terriers age 5 times as fast and Akkadian retrievers age 4 times as fast. If Dan bought a newborn Akkadian on January 1, 2010, a newborn Khazarian 1 year later, and a newborn Livonian 1 year after that, in what year will the sum of the dogyear ages of the Akkadian and the Khazarian first be exceeded by twice the age of the Livonian in dog years, rounding all ages down to the nearest integer?
A. 2013 B. 2014 C. 2015 D. 2016 E. 2017
Kudos for a correct solution. MANHATTAN GMAT OFFICIAL SOLUTION:Create a variable to represent calendar (human) years since January 1, 2012 (the date of the final purchase). If t = 0 in 2012 and 1 in 2013, then t = calendar year since 2012. Now you can write functions to give you dogages for each breed as a function of t. Akkadian’s age A(t) = 4t + 8 (since the Akkadian is now 4 × 2 = 8 dogyears old on January 1, 2012) Khazarian’s age K(t) = 5t + 5 (the second 5 is for the one calendar year, or 5 dogyears for the Khazarian, since 2011) Livonian’s age L(t) = 7t The sum of A and K is 9t + 13. Twice L is 14t. We are looking for the t at which the sum (9t + 13) is first exceeded by 14t. So the inequality we’re looking for is this: 14t > 9t + 13 5t > 13 t > 2.6 The smallest integer t for which this is true is 3, so the calendar year = 2012 + 3 = 2015. The correct answer is C.
_________________
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



NonHuman User
Joined: 09 Sep 2013
Posts: 7775

Re: Different breeds of dogs get older at different rates in “dog years.”
[#permalink]
Show Tags
12 Dec 2017, 13:36
Hello from the GMAT Club BumpBot! Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up  doing my job. I think you may find it valuable (esp those replies with Kudos). Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Books  GMAT Club Tests  Best Prices on GMAT Courses  GMAT Mobile App  Math Resources  Verbal Resources




Re: Different breeds of dogs get older at different rates in “dog years.” &nbs
[#permalink]
12 Dec 2017, 13:36






