Find all School-related info fast with the new School-Specific MBA Forum

It is currently 02 Jul 2015, 08:36

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Jack is now 14 years older than Bill. If in 10 years Jack

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Manager
Manager
avatar
Joined: 02 Dec 2012
Posts: 178
Followers: 3

Kudos [?]: 826 [0], given: 0

Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 20 Dec 2012, 04:47
3
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

72% (02:15) correct 28% (01:29) wrong based on 473 sessions
Jack is now 14 years older than Bill. If in 10 years Jack will be twice as old as Bill, how old will Jack be in 5 years?

(A) 9
(B) 19
(C) 21
(D) 23
(E) 33
[Reveal] Spoiler: OA
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 28247
Followers: 4463

Kudos [?]: 45027 [1] , given: 6638

Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 20 Dec 2012, 04:50
1
This post received
KUDOS
Expert's post
Walkabout wrote:
Jack is now 14 years older than Bill. If in 10 years Jack will be twice as old as Bill, how old will Jack be in 5 years?

(A) 9
(B) 19
(C) 21
(D) 23
(E) 33


Currently: J = B + 14;
In 10 year: J + 10 = 2(B + 10);

Solving gives J = 18;

Thus in 5 years Jack will be 18 + 5 = 23 years old.

Answer: D.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Manager
Manager
User avatar
Joined: 12 Jan 2013
Posts: 249
Followers: 2

Kudos [?]: 34 [0], given: 47

GMAT ToolKit User
Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 10 Jan 2014, 01:57
Walkabout wrote:
Jack is now 14 years older than Bill. If in 10 years Jack will be twice as old as Bill, how old will Jack be in 5 years?

(A) 9
(B) 19
(C) 21
(D) 23
(E) 33



Set up the equations: [J = B + 14] and [J + 10 = 2(B + 10)], subtract the two and solve for B, this gives us B = 4.. From the first equation we know that Jack is 14 years older than Bill today, which means that Jack is 14 + 4 = 18 years old.. So naturally, in 5 years he's 23 years old.
Intern
Intern
avatar
Joined: 08 Oct 2013
Posts: 1
Followers: 0

Kudos [?]: 0 [0], given: 23

Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 09 Jun 2014, 13:52
Bunuel wrote:
Walkabout wrote:
Jack is now 14 years older than Bill. If in 10 years Jack will be twice as old as Bill, how old will Jack be in 5 years?

(A) 9
(B) 19
(C) 21
(D) 23
(E) 33


Currently: J = B + 14;
In 10 year: J + 10 = 2(B + 10);

Solving gives J = 18;

Thus in 5 years Jack will be 18 + 5 = 23 years old.

Answer: D.


We know that J = B + 14

B = J + 14

So to add 10 to both sides, we get

J + 10 = 2 ( B + 14 ) + 10

Why should we have 2 ( B + 10 ) ?



Thanks,
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 28247
Followers: 4463

Kudos [?]: 45027 [0], given: 6638

Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 09 Jun 2014, 14:32
Expert's post
Abraham00 wrote:
Bunuel wrote:
Walkabout wrote:
Jack is now 14 years older than Bill. If in 10 years Jack will be twice as old as Bill, how old will Jack be in 5 years?

(A) 9
(B) 19
(C) 21
(D) 23
(E) 33


Currently: J = B + 14;
In 10 year: J + 10 = 2(B + 10);

Solving gives J = 18;

Thus in 5 years Jack will be 18 + 5 = 23 years old.

Answer: D.


We know that J = B + 14

B = J + 14

So to add 10 to both sides, we get

J + 10 = 2 ( B + 14 ) + 10

Why should we have 2 ( B + 10 ) ?



Thanks,


First of all, from J = B + 14, we get that B = J - 14, not B = J + 14.

Next, we are told that in 10 years Jack will be twice as old as Bill: in 10 years, Jack will J + 10 years and Bill will be B + 10 years. So, J + 10 = 2(B + 10).

Hope it's clear.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Kellogg Thread Master
avatar
Joined: 12 Jun 2014
Posts: 129
Location: India
Concentration: General Management, Technology
GMAT 1: 740 Q49 V41
WE: Information Technology (Consulting)
Followers: 9

Kudos [?]: 39 [0], given: 38

Reviews Badge
Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 15 Jul 2014, 11:09
I did this using number substitution. When we set up J=B+14, and we want to know J+5, we can safely say we want B+19 here. Since B cannot be zero, a and b are ruled out. Then you substitute the remaining values, starting from the middle one, which is 23. And you get the answer.
1 KUDOS received
Intern
Intern
avatar
Joined: 13 Dec 2013
Posts: 40
Schools: Fuqua (I), AGSM '16
GMAT 1: 620 Q42 V33
Followers: 2

Kudos [?]: 10 [1] , given: 10

GMAT ToolKit User
Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 22 Aug 2014, 14:11
1
This post received
KUDOS
Interpreting the 2nd equation could get tricky.

I recommend using POE. It takes less than 1min.

Start with B since A seems a bit too young.

b) 19 - 5 = Jack is 14 now and and therefore Bill is 0 years old. NEXT

c) 21 - 5 = Jack is 16 and Bill is 2. Then, in 10 years Jack will be 26 and Bill 12. That is not twice the age as stated, so move on to the next one.

d) 23 - 5 = 18 and Bill is 4. Then, in 10 years Jack will be 28 and Bill 14. CORRECT.
Intern
Intern
avatar
Joined: 25 Jan 2015
Posts: 1
Followers: 0

Kudos [?]: 0 [0], given: 2

Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 14 Jun 2015, 16:28
Thinking out the problem conceptually you can solve the problem quite quickly in your head(or paper):

1) If Jack is twice as old as Bill in 10 years then the difference between the two ages(at that time) is equal to Bill's age! Since they are 14 years apart (always), Bill is currently 4 and Jack 18.
2)18+5 = 23 -->(D)

No more than 30 seconds to solve this way
Expert Post
1 KUDOS received
Optimus Prep Instructor
User avatar
Joined: 06 Nov 2014
Posts: 339
Followers: 3

Kudos [?]: 65 [1] , given: 2

Re: Jack is now 14 years older than Bill. If in 10 years Jack [#permalink] New post 17 Jun 2015, 07:31
1
This post received
KUDOS
Expert's post
Jack is now 14 years older than Bill. If in 10 years Jack will be twice as old as Bill, how old will Jack be in 5 years?

J+5 = ?
J = B + 14 => B = J - 14
J + 10 = 2 (B + 10) => J + 10 = 2B + 20 => J= 2B + 10
J = 2(J-14) + 10
J = 2J - 28 + 10
J = 2J -18
J = 18
=> 18 + 5
(A) 9
(B) 19
(C) 21
(D) 23
(E) 33
_________________

Cassandra Wolff
Customer Support | Optimus Prep
 
Facebook Linkedin Youtube Twitter slideshare Google+
 

Re: Jack is now 14 years older than Bill. If in 10 years Jack   [#permalink] 17 Jun 2015, 07:31
    Similar topics Author Replies Last post
Similar
Topics:
Experts publish their posts in the topic Larry is 5 years older than Moe, and curly is twice as old a scraby07 2 01 Jan 2014, 07:44
Experts publish their posts in the topic John is 20 years older than Brian. 12 years ago, John was carcass 1 07 May 2012, 03:07
3 Experts publish their posts in the topic A town's oldest inhabitant is x years older than the sum of the ages mustu 5 17 Jul 2011, 05:12
26 Experts publish their posts in the topic It takes Jack 2 more hours than Tom to type 20 pages. If Barkatis 18 04 Aug 2010, 18:09
8 Experts publish their posts in the topic Roy is now 4 years older than Erik and half of that amount AtifS 7 14 Feb 2010, 00:56
Display posts from previous: Sort by

Jack is now 14 years older than Bill. If in 10 years Jack

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.