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Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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17 Oct 2017, 22:31
Question Stats:
84% (01:29) correct 16% (02:03) wrong based on 82 sessions
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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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18 Oct 2017, 01:27
Let jim daughter be d Jim son be x X8=2d8 X=d+5 d+58=2d8 d3=2dd d=5 A is correct Sent from my InfinixX600 using GMAT Club Forum mobile app



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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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18 Oct 2017, 01:39
EQ 1 Jim's son = S Jim's Daughter = D (S8)= 2 (D8) S8 = 2D 16 S2D= 8 EQ2 S= D+5 or S D = 5 Equating eq 1 and 2
D=13



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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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18 Oct 2017, 10:16
s=son's age now d=daughter's age now (s8)/(d8)=2 sd=5 solve about equations: d=13 (C) Sent from my SMG935W8 using GMAT Club Forum mobile app



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Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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18 Oct 2017, 14:09
Bunuel wrote: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If Jim’s son is now 5 years older than his daughter, how old is Jim’s daughter now?
(A) 5 (B) 10 (C) 13 (D) 16 (E) 18 Exactly 8 years ago, Jim’s son, S, was twice as old as Jim’s daughter, D S  8 = 2(D  8) Son is now five years older than daughter: S = D + 5 Substitute for S in first equation (D + 5)  8 = 2(D  8) D  3 = 2D  16 D = 13 (Check: D is 13 now; 8 years she ago was 5. S is 18 now (= D + 5), so 8 years ago he was 10. 10 = twice as old as 5, back then. Correct.) Answer C



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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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19 Oct 2017, 02:47
ewmike wrote: Let jim daughter be d Jim son be x X8=2d8 X=d+5 d+58=2d8 d3=2dd d=5 A is correct
Hi, There is an errot here. You did not mulyply 2 * 8 too. it should be 2 (d 8) = 2d  16



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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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23 Oct 2017, 10:11
I set the original equation up as (s8)=2(d16), which simplifies to s8=2d16. we are given s=d+5, so I substitute that in for s. d3=2d16, simplified d=13. Initially, I made a small mistake and got d=5, quickly checking my math, I realized the daughter cannot be 5 because 8 years ago she wasn't born yet. So I redid it until I figured out my mistake. I wasted a lot of time on something pretty simple here. Simple mistakes are my biggest problem, I know the material pretty well, but I just make a lot of dumb errors. Any guidance would be appreciated.
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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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23 Oct 2017, 10:55
If Son = X Daughter=X5
EQ: x8=2(X58) X8=2X26 X=18
Daughter = 185= 13
Answer is C



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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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24 Oct 2017, 05:06
Bunuel wrote: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If Jim’s son is now 5 years older than his daughter, how old is Jim’s daughter now?
(A) 5 (B) 10 (C) 13 (D) 16 (E) 18 We can let Jim’s son’s current age = s and Jim’s daughter’s current age = d. We can also state that 8 years ago, his son was (s  8) years old and his daughter was (d  8) years old. We can create the following equation: s  8 = 2(d  8) s  8 = 2d  16 s = 2d  8 and s = 5 + d Thus: 2d  8 = 5 + d d = 13 Answer: C
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Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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26 Oct 2017, 02:49
we can also check from answer choices if we are unable to form the equation. Start from C Let Jim's daughter's age be 13 today Jim's son age today will be 13+5=18 Now 8 years ago the son was 2 times the age of the daughter. find the age of both of them 8 years ago Daughter=138=5 Son=188=10 Now 10 =2x5=10=Answer C



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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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28 Aug 2018, 05:56
Bunuel wrote: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If Jim’s son is now 5 years older than his daughter, how old is Jim’s daughter now?
(A) 5 (B) 10 (C) 13 (D) 16 (E) 18 Jim’s son is now 5 years older than his daughterLet D = the daughter's age NOW So D + 5 = the son's age NOW This also means that D  8 = the daughter's age EIGHT YEARS AGO This also means that D + 5  8 = the son's age EIGHT YEARS AGO Or we can say, D  3 = the son's age EIGHT YEARS AGO 8 years ago, Jim’s son was twice as old as Jim’s daughter.8 years ago, the daughter's age was D  8 and the son's age was D  3So, we can write: D  3 = 2( D  8) Expand right side to get: D  3 = 2D  16 Solve to get D = 13 Since D = the daughter's present age, the correct answer is C Cheers, Brent
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Re: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If
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28 Aug 2018, 06:11
Bunuel wrote: Exactly 8 years ago, Jim’s son was twice as old as Jim’s daughter. If Jim’s son is now 5 years older than his daughter, how old is Jim’s daughter now?
(A) 5 (B) 10 (C) 13 (D) 16 (E) 18 \(? = D\) \(\left\{ \begin{gathered} \left( {S  8} \right) = 2\left( {D  8} \right) \hfill \\ S = D + 5 \hfill \\ \end{gathered} \right.\,\,\,\,\,\,\,\, \sim \,\,\,\,\,\,\,\left\{ \begin{gathered} \left( {S  8} \right) = 2\left( {D  8} \right) \hfill \\ \left( {S  \underline 8 } \right) = \left( {D  \underline 8 } \right) + 5 \hfill \\ \end{gathered} \right.\,\,\,\,\,\,\,\,\mathop \Rightarrow \limits^{\left( {\,  \,} \right)} \,\,\,\,\,\,\,\,\left( {D  8} \right)  5 = 0\,\,\,\,\,\,\,\, \Rightarrow \,\,\,\,\,\,? = D = 13\) The above follows the notations and rationale taught in the GMATH method.
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