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Jane started babysitting when she was 18 years old.
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Jane started babysitting when she was 18 years old. Whenever she babysat for a child, that child was no more than half her age at the time. Jane is currently 32 years old, and she stopped babysitting 10 years ago. What is the current age of the oldest person for whom Jane could have babysat? A. 20 B. 21 C. 22 D. 23 E. 24
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Originally posted by u0422811 on 05 Jun 2011, 14:05.
Last edited by Bunuel on 02 Oct 2013, 09:56, edited 2 times in total.
Edited the OA.




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Re: Jane babysitting
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19 Mar 2012, 06:32
GMATD11 wrote: subhashghosh wrote: When she sat initially Jane's age = 18, and the child's max age = 9
10 yrs back, she was 22 yrs old, so the child's age max age possible = 22/2 = 11
So the child would be now 22 + 10 = 21 yrs old
Answer  B I got the answer right but Jane started baby sitting at 18 max age of child at that time will be 9 Jane left baby sitting at the age of 22 At that time age of child will be 11 As current age of jane is 32 Current age of child will be 11+10=21 I want to discuss the trap answer 23 Jane started baby sitting at 18 max age of child at that time will be 9 As current age of jane is 32 Current age of child will be 9+14=23 Take away we need to imply the statement as mentioned in the Word Problem. M i correct... Basically i also want to discuss the strategy for solving Word Problems Generally I write as i read any implied statement and following this strategy since childhood & comfortable with it.But my friend told that your strategy is wrong. Pls comment D (23) is not a trap answer, it's a correct answer. Jane started babysitting when she was 18 years old. Whenever she babysat for a child, that child was no more than half her age at the time. Jane is currently 32 years old, and she stopped babysitting 10 years ago. What is the current age of the oldest person for whom Jane could have babysat?A. 20 B. 21 C. 22 D. 23 E. 24 Check two extreme cases: Jane = 18, child = 9, years ago = 3218 = 14 > child's age now = 9+14 = 23; Jane = 22, child = 11, years ago = 3222 = 10 > child's age now = 11+10 = 21. Answer: D.
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Jane babysitting
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05 Jun 2011, 14:39
u0422811 wrote: Jane started babysitting when she was 18 years old. Whenever she babysat for a child, that child was no more than half her age at the time. Jane is currently 32 years old, and she stopped babysitting 10 years ago. What is the current age of the oldest person for whom Jane could have babysat?
(a) 20 (b) 21 (c) 22 (d) 23 (e) 24
Jane's Age Then  Oldest Child's Age Then  Years Elapsed so far  The same Child's Age now  18  9  14  9+14=23  19  9.5  13  9.5+13=22.5  20  10  12  10+12=22  21  10.5  11  10.5+11=21.5  22  11  10  11+10=21 
Now, The current age of the oldest person among the people she ever babysat=23 The current age of the oldest person she ever babysat=21 Ans: "B"




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Re: Jane babysitting
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05 Jun 2011, 19:16
When she sat initially Jane's age = 18, and the child's max age = 9 10 yrs back, she was 22 yrs old, so the child's age max age possible = 22/2 = 11 So the child would be now 22 + 10 = 21 yrs old Answer  B
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Re: Jane babysitting
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06 Jun 2011, 00:32
first: read question carefully the trap is between answer 23 and 21, and trap is Quote: What is the current age of the oldest person for whom Jane could have babysat ? so simply she could have baby sat oldest person at 22 years of age \((3210)\) \(=> 22/2 = 11\) 10 years hence \(11 +10 = 21\)(current age of person) hence answer is B Quote: you may find yourself trapped for 23 / choice D if you donot read stimulus carefully
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Re: Good Word Problem
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Updated on: 12 Jun 2011, 05:38
u0422811 wrote: Jane started babysitting when she was 18 years old. Whenever she babysat for a child, that child was no more than half her age at the time. Jane is currently 32 years old, and she stopped babysitting 10 years ago. What is the current age of the oldest person for whom Jane could have babysat?
(a) 20 (b) 21 (c) 22 (d) 23 (e) 24 As far as I remember think the OA has to be D. when Jane was 18 = the child was 9 yrs old after 14 years 9+14 = 23 .. the question is asking oldest person (now) , for whom jane have baby sat. The question isn't asking the oldest person ( at the point of baby sitting), for whom Jane baby sat. In this case it would have been 21(11+10) PS: Attached the MGMAT answer
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Originally posted by sudhir18n on 11 Jun 2011, 22:07.
Last edited by sudhir18n on 12 Jun 2011, 05:38, edited 1 time in total.



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Re: Good Word Problem
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11 Jun 2011, 22:30
sudhir18n wrote: u0422811 wrote: Jane started babysitting when she was 18 years old. Whenever she babysat for a child, that child was no more than half her age at the time. Jane is currently 32 years old, and she stopped babysitting 10 years ago. What is the current age of the oldest person for whom Jane could have babysat?
(a) 20 (b) 21 (c) 22 (d) 23 (e) 24 As far as I remember think the OA has to be D. when Jane was 18 = the child was 9 yrs old after 14 years 9+14 = 23 .. the question is asking oldest person (now) , for whom jane have baby sat. The question isn't asking the oldest person ( at the point of baby sitting), for whom Jane baby sat. In this case it would have been 21(11+10) But the Question is asking for whom Jane could have babysat?
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Re: Jane babysitting
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12 Jun 2011, 09:21
I got D too. When Jane was 18 yrs old, the child would have been no more than 9 yrs old. Now after 14 yrs Jane is 18+14 = 32 Child is 9 + 14 = 23



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Re: Jane babysitting
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12 Jun 2011, 09:44
I agree with @sudhir18n 's reply.
when jane is 18, the oldest she could have baby sat = 9 yr old
as jane is 32 . i.e after 14 years that oldest baby would be 9+14 = 23
Answer is 23 D.
there is another post out there where they are asking for youngest .
if the question is asking for youngest then answer is 21 . if its asking for oldest then it got to be 23.
Old post: Jane started babysitting when she was 18 years old, however, she only babysat children that were, at most, half her age. Jane is currently 32 years old, and she stopped babysitting ten years ago. What is the current age of the youngest child that Jane could have babysat?



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Re: Jane babysitting
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13 Jun 2011, 00:35
at 18, max age of child = 9. at 22,max age of child = 11.
thus adding 10 years to this = 21 yrs.



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Re: Jane babysitting
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19 Mar 2012, 06:09
subhashghosh wrote: When she sat initially Jane's age = 18, and the child's max age = 9
10 yrs back, she was 22 yrs old, so the child's age max age possible = 22/2 = 11
So the child would be now 22 + 10 = 21 yrs old
Answer  B I got the answer right but Jane started baby sitting at 18 max age of child at that time will be 9 Jane left baby sitting at the age of 22 At that time age of child will be 11 As current age of jane is 32 Current age of child will be 11+10=21 I want to discuss the trap answer 23 Jane started baby sitting at 18 max age of child at that time will be 9 As current age of jane is 32 Current age of child will be 9+14=23 Take away we need to imply the statement as mentioned in the Word Problem. M i correct... Basically i also want to discuss the strategy for solving Word Problems Generally I write as i read any implied statement and following this strategy since childhood & comfortable with it.But my friend told that your strategy is wrong. Pls comment



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Re: Jane babysitting
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19 Mar 2012, 07:41
Bunuel wrote: GMATD11 wrote: subhashghosh wrote: When she sat initially Jane's age = 18, and the child's max age = 9
10 yrs back, she was 22 yrs old, so the child's age max age possible = 22/2 = 11
So the child would be now 22 + 10 = 21 yrs old
Answer  B I got the answer right but Jane started baby sitting at 18 max age of child at that time will be 9 Jane left baby sitting at the age of 22 At that time age of child will be 11 As current age of jane is 32 Current age of child will be 11+10=21 I want to discuss the trap answer 23 Jane started baby sitting at 18 max age of child at that time will be 9 As current age of jane is 32 Current age of child will be 9+14=23 Take away we need to imply the statement as mentioned in the Word Problem. M i correct... Basically i also want to discuss the strategy for solving Word Problems Generally I write as i read any implied statement and following this strategy since childhood & comfortable with it.But my friend told that your strategy is wrong. Pls comment D (23) is not a trap answer, it's a correct answer. Jane started babysitting when she was 18 years old. Whenever she babysat for a child, that child was no more than half her age at the time. Jane is currently 32 years old, and she stopped babysitting 10 years ago. What is the current age of the oldest person for whom Jane could have babysat?A. 20 B. 21 C. 22 D. 23 E. 24 Check two extreme cases: Jane = 18, child = 9, years ago = 3218 = 14 > child's age now = 9+14 = 23; Jane = 22, child = 11, years ago = 3222 = 10 > child's age now = 11+10 = 21. Answer: D. Thanks Bunuel Whats the best strategy for solving Word Problems.



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Re: Jane babysitting
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19 Mar 2012, 07:44
GMATD11 wrote: Thanks Bunuel
Whats the best strategy for solving Word Problems. It really depends on the question itself, there is no general "best strategy". Check this: wordproblemsmadeeasy87346.html, it might helps in word translation.
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Re: Jane started babysitting when she was 18 years old.
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19 Mar 2012, 13:26
if when she was 18, a kid was 9 (half of her age), then at the age 22 (3210) that kid will be 11 years old (22*9)/18 11+10=21
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Re: Jane started babysitting when she was 18 years old.
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02 Jul 2013, 01:16
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Re: Jane started babysitting when she was 18 years old.
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23 Feb 2015, 14:08
Hi melissamartin, This question comes with a minor "twist"  you have to account for the number of years SINCE Jane babysat any of those children. We're told that that the children were no more than HALF of Jane's age at the time AND we have to account for the change in time since Jane babysat each child. When Jane was.... 18....the oldest a child could have been was 9. Since that was 14 years ago, the child would now be 9+14 = 23 20....the oldest a child could have been was 10, but that was 12 years ago, so the child would now be 10+12 = 22 22....the oldest a child could have been was 11, but that was 10 years ago, so the child would now be 11+10 = 21 This oldest that any of those children could be NOW is 23. Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: Jane started babysitting when she was 18 years old.
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01 Jul 2017, 08:54
The question clearly says that the age of the child is no more than half of Janes age at the time of baby sitting. So The age of 18 years the oldest child whom she baby sat was < 9 years so the maximum age is 8 and the maximum age of the oldest child when she baby sat The age of 22 is < 11 years. Where am I going wrong in my understanding of the problem??



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Re: Jane started babysitting when she was 18 years old.
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01 Jul 2017, 09:26
muthappashivani wrote: The question clearly says that the age of the child is no more than half of Janes age at the time of baby sitting. So The age of 18 years the oldest child whom she baby sat was < 9 years so the maximum age is 8 and the maximum age of the oldest child when she baby sat The age of 22 is < 11 years. Where am I going wrong in my understanding of the problem?? No no more than half her age does not mean less than half her age. The correct relationship is \(\{baby's \ age\} \leq \frac{\{Jane's \ age\}}{2}\).
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Jane started babysitting when she was 18 years old.
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14 Feb 2018, 14:35
i think wording of the question matters very much. Had the question been, what is current age of oldest child, she could have babysat, then answer is 21. (Even i fell for this) but actual question is , what is current age of oldest person, she could have babysat, then answer is 23 (as shown above) Need to have my eyes wide open



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Re: Jane started babysitting when she was 18 years old.
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Re: Jane started babysitting when she was 18 years old.
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