GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 22 Sep 2018, 06:39

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.

Close

Request Expert Reply

Confirm Cancel

A certain family has 3 sons: Richard is 6 years older than David, and

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Intern
Intern
avatar
Joined: 05 Nov 2011
Posts: 15
Location: France, Metropolitan
GMAT ToolKit User
A certain family has 3 sons: Richard is 6 years older than David, and  [#permalink]

Show Tags

New post 17 Feb 2015, 03:42
1
4
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

75% (01:58) correct 25% (02:14) wrong based on 169 sessions

HideShow timer Statistics

A certain family has 3 sons: Richard is 6 years older than David, and David is 8 years older than Scott. If in 8 years, Richard will be twice as old as Scott, then how old was David 4 years ago?

(A) 8
(B) 10
(C) 12
(D) 14
(E) 16
SVP
SVP
User avatar
P
Joined: 08 Jul 2010
Posts: 2334
Location: India
GMAT: INSIGHT
WE: Education (Education)
Reviews Badge
Re: A certain family has 3 sons: Richard is 6 years older than David, and  [#permalink]

Show Tags

New post 17 Feb 2015, 04:46
2
Stardust Chris wrote:
A certain family has 3 sons: Richard is 6 years older than David, and David is 8 years older than Scott. If in 8 years, Richard will be twice as old as Scott, then how old was David 4 years ago?

(A) 8
(B) 10
(C) 12
(D) 14
(E) 16


Let's say
Age of Richard is "R"
Age of David is "D"
Age of Scott is "S"

Now
Richard is 6 years older than David,
i.e. R = D +6

David is 8 years older than Scott
i.e. D = S +8

If in 8 years, Richard will be twice as old as Scott
i.e. R+8 = 2x(S+8)
i.e. R+8 = 2S + 16
i.e. R = 2S+8

But R = D+6 = (S+8)+6 = S+14

therefore, 2S + 8 = S +14
i.e. S = 6
i.e. R = 20
i.e. D = 14

Now,
how old was David 4 years ago?

i.e. D-4 = 14-4 = 10 years

Answer: Option
_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

DS Forum Moderator
avatar
P
Joined: 22 Aug 2013
Posts: 1343
Location: India
Premium Member
Re: A certain family has 3 sons: Richard is 6 years older than David, and  [#permalink]

Show Tags

New post 20 May 2017, 02:33
R is 6 years older than D, D is 8 years older than S
So R is (6+8)=14 years older than S, so we can say that R = S + 14

After 8 years, age of Scott = S+8, age of Richard = S+8+14 = S+22 (difference will always be 14 years as long as both are alive)
Given: S+22 = 2*(S+8)
Solve to get S=6

Thus currently S is 6 years, 4 years ago S would have been 2 years old, and David must have been 2+8 = 10 years old (difference between their ages would have been same then as now)

Hence answer is B
Manager
Manager
avatar
B
Joined: 25 May 2016
Posts: 77
Location: Singapore
Concentration: Finance, General Management
GMAT 1: 620 Q46 V30
Re: A certain family has 3 sons: Richard is 6 years older than David, and  [#permalink]

Show Tags

New post 30 Jun 2018, 08:17
You shd draw a model to visualize their ages.

Scott + 14 + 8 = 2 (Scott + 8)
Scott = 6 years
David = 14 years.
4 years ago, David was 10 years old.

Answer : B
_________________

7 Kudos left to unlock next level. Help me by Contributing one for cause :) .. Please

Manick9

If you found my post helpful, kindly press "+1 Kudos" to appreciate

Re: A certain family has 3 sons: Richard is 6 years older than David, and &nbs [#permalink] 30 Jun 2018, 08:17
Display posts from previous: Sort by

A certain family has 3 sons: Richard is 6 years older than David, and

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Events & Promotions

PREV
NEXT


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

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.