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100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote ## Jim is twice as old as Fred ... ##### This topic has 2 expert replies and 4 member replies ## Jim is twice as old as Fred ... Jim is twice as old as Fred, and Sam is 2 years younger than Fred. Four years ago Jim was 4 times as old as Sam. How old is Jim now ? What is the best and quickest way to work this out ? Thanks. II Master | Next Rank: 500 Posts Joined 14 Nov 2007 Posted: 214 messages Upvotes: 15 Target GMAT Score: 650+ Jim 2x Fred x Sam x-2 Four years ago 2x - 4 = 4(x-2-4) x comes to 10 So Jim should be 20 Senior | Next Rank: 100 Posts Joined 06 Dec 2007 Posted: 78 messages Upvotes: 2 Test Date: Jan 25th Target GMAT Score: 700 sujaysolanki wrote: Jim 2x Fred x Sam x-2 Four years ago 2x - 4 = 4(x-2-4) x comes to 10 So Jim should be 20 I was wondering if when they "four years ago Jim was 4 times as old as Sam" Are they referring to Sam's Current age or Sam's age 4 years ago? Master | Next Rank: 500 Posts Joined 10 Dec 2007 Posted: 400 messages Upvotes: 19 Target GMAT Score: 700 GMAT Score: 680 preciousrain7 wrote: sujaysolanki wrote: Jim 2x Fred x Sam x-2 Four years ago 2x - 4 = 4(x-2-4) x comes to 10 So Jim should be 20 I was wondering if when they "four years ago Jim was 4 times as old as Sam" Are they referring to Sam's Current age or Sam's age 4 years ago? Thats a good point ! I understood it to be Sam's age 4 years ago. Legendary Member Joined 05 Sep 2007 Posted: 645 messages Followed by: 5 members Upvotes: 34 Quote: I was wondering if when they "four years ago Jim was 4 times as old as Sam" Are they referring to Sam's Current age or Sam's age 4 years ago? preciousrain7, it should be compared with Sam's age 4 years ago otherwise it will be mentioned in the Qs to compare Jim's age 4yrs ago with Sam's current age! _________________ Correct me If I am wrong Regards, Amitava ### GMAT/MBA Expert GMAT Instructor Joined 08 Dec 2008 Posted: 13046 messages Followed by: 1253 members Upvotes: 5254 GMAT Score: 770 I've added the answer choices.... II wrote: Jim is twice as old as Fred, and Sam is 2 years younger than Fred. Four years ago Jim was 4 times as old as Sam. How old is Jim now ? A. 8 B. 12 C. 16 D. 20 E. 24 TODAY'S AGES Today Jim is twice as old as Fred, and Sam is 2 years younger than Fred. Let x = Fred's age TODAY So, 2x = Jim's age TODAY And x - 2 = Sam's age TODAY AGES FOUR YEARS AGO Let's first determine Jim's age and Sam's age FOUR YEARS AGO If 2x = Jim's age TODAY, then 2x - 4 = Jim's age FOUR YEARS AGO If x - 2 = Sam's age TODAY, then x - 2 - 4 = Sam's age FOUR YEARS AGO Four years ago Jim was 4 times as old as Sam. In other words, the value of 2x - 4 is 4 times the value of x - 2 - 4 So, we can write: 2x - 4 = 4(x - 2 -4) Simplify right side: 2x - 4 = 4(x - 6) Expand right side: 2x - 4 = 4x - 24 Add 24 to both sides: 2x + 20 = 4x Subtract 2x from both sides: 20 = 2x Solve: x = 10 How old is Jim NOW? 2x = Jim's age TODAY Since x = 10, we know that Jim's age = 2(10) = 20 Answer: D Cheers, Brent _________________ Brent Hanneson â€“ Creator of GMATPrepNow.com Use my video course along with Sign up for free Question of the Day emails And check out all of these free resources GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMATâ€™s FREE 60-Day Study Guide and reach your target score in 2 months! ### GMAT/MBA Expert GMAT Instructor Joined 25 Apr 2015 Posted: 2950 messages Followed by: 19 members Upvotes: 43 II wrote: Jim is twice as old as Fred, and Sam is 2 years younger than Fred. Four years ago Jim was 4 times as old as Sam. How old is Jim now ? What is the best and quickest way to work this out ? Thanks. II We can let J, S, and F = the current age of Jim, Fred, and Sam, respectively, and create the equations: J = 2F and S = F - 2 S + 2 = F and J - 4 = 4(S - 4) J - 4 = 4S - 16 J = 4S - 12 Since J = 2F we have: 2F = 4S - 12 F = 2S - 6 Since S + 2 = F, we have: S + 2 = 2S - 6 8 = S So J = 4 x 8 - 12 = 20. _________________ Scott Woodbury-Stewart Founder and CEO scott@targettestprep.com See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews • Free Practice Test & Review How would you score if you took the GMAT Available with Beat the GMAT members only code • 5 Day FREE Trial Study Smarter, Not Harder Available with Beat the GMAT members only code • FREE GMAT Exam Know how you'd score today for$0

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