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In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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Updated on: 31 May 2013, 00:53
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In the decimal 3.1de, d and e each represent a digit. If x represents the decimal 3.1de rounded to the nearest tenth, what is the value of x? (1) d=4 (2) e=8
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Originally posted by raviram80 on 20 May 2012, 21:51.
Last edited by Bunuel on 31 May 2013, 00:53, edited 3 times in total.
Renamed the topic and edited the question.



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Re: Rounded to nearest tenth [#permalink]
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20 May 2012, 22:20
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1. d=4.. so the number is 3.14e...... we are suppose to round off to the nearest tenth....so tenth digit is 4 which will be rounded off to 3.1....we are not bothered about e.
2. e= 8
Here the number can be 3.118 whcih will be rounded off to 3.1 or 3.158 which will be rounded off to 3.2......as we are not sure of the value of d we are not sure ...it can have different values.
so the correct answer is A



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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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22 May 2012, 08:38
raviram80 wrote: In the decimal 3.1de, d and e each represent a digit. If x represents the decimal 3.1de rounded to the nearest tenth, what is the value of
(1) d=4 (2) e=8
Folks,
could you clarify this question, I thought E but Gmat prep software says A. I am confused.
Thanks We need to find out whether d belongs to 04 category or 59 category. We get this from i) but not from ii). So, A



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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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06 Jul 2012, 03:27
Shouldn't the answer be C: both needed to answer.
Since d is 4 as per statement 1, the approximation also depends on e. If e=0  4, then x is 3.1. If e=5  9, then the x is 3.2. e would not matter only if d < 4.



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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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06 Jul 2012, 04:43
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ga99 wrote: Shouldn't the answer be C: both needed to answer.
Since d is 4 as per statement 1, the approximation also depends on e. If e=0  4, then x is 3.1. If e=5  9, then the x is 3.2. e would not matter only if d < 4. Rounding rulesRounding is simplifying a number to a certain place value. To round the decimal drop the extra decimal places, and if the first dropped digit is 5 or greater, round up the last digit that you keep. If the first dropped digit is 4 or smaller, round down (keep the same) the last digit that you keep.Example: 5.3485 rounded to the nearest tenth = 5.3, since the dropped 4 is less than 5. 5.3485 rounded to the nearest hundredth = 5.35, since the dropped 8 is greater than 5. 5.3485 rounded to the nearest thousandth = 5.349, since the dropped 5 is equal to 5. BACK TO THE ORIGINAL QUESTION: In the decimal 3.1de, d and e each represent a digit. If x represents the decimal 3.1de rounded to the nearest tenth, what is the value of x?According to the rule above the tenth digit of x depends only on d, since it's the first dropped digit. (1) d=4. Our decimal is 3.14e > the first dropped digit is 4, so less than 5, hence 3.14e rounded to the nearest tenth is 3.1. Sufficient. (2) e=8. Clearly not sufficient. Answer: A. Hope it's clear.
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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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06 Jul 2012, 06:31
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Its clear now. I was always rounding based on all the digits from right to left and not taking just the first dropped digit. For e.g. in your example of "5.3485 rounded to the nearest tenth = 5.3, since the dropped 4 is less than 5." I would always have picked 5.4 I now see how that might not work. Thanks for the explanation. I overlooked this while preparing. Bunuel wrote: ga99 wrote: Shouldn't the answer be C: both needed to answer.
Since d is 4 as per statement 1, the approximation also depends on e. If e=0  4, then x is 3.1. If e=5  9, then the x is 3.2. e would not matter only if d < 4. Rounding rulesRounding is simplifying a number to a certain place value. To round the decimal drop the extra decimal places, and if the first dropped digit is 5 or greater, round up the last digit that you keep. If the first dropped digit is 4 or smaller, round down (keep the same) the last digit that you keep.Example: 5.3485 rounded to the nearest tenth = 5.3, since the dropped 4 is less than 5. 5.3485 rounded to the nearest hundredth = 5.35, since the dropped 8 is greater than 5. 5.3485 rounded to the nearest thousandth = 5.349, since the dropped 5 is equal to 5. BACK TO THE ORIGINAL QUESTION: In the decimal 3.1de, d and e each represent a digit. If x represents the decimal 3.1de rounded to the nearest tenth, what is the value ofAccording to the rule above the tenth digit of x depends only on d, since it's the first dropped digit. (1) d=4. Our decimal is 3.14e > the first dropped digit is 4, so less than 5, hence 3.14e rounded to the nearest tenth is 3.1. Sufficient. (2) e=8. Clearly not sufficient. Answer: A. Hope it's clear.



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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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23 May 2013, 08:37
raviram80 wrote: In the decimal 3.1de, d and e each represent a digit. If x represents the decimal 3.1de rounded to the nearest tenth, what is the value of
(1) d=4 (2) e=8
Folks,
could you clarify this question, I thought E but Gmat prep software says A. I am confused.
Thanks dude here is the logic if d = 4, then when u round it, we do get a value of 3.2 so its sufficient 2. s2 is not sufficient. hence a is fine



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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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09 Jul 2015, 12:05
raviram80 wrote: In the decimal 3.1de, d and e each represent a digit. If x represents the decimal 3.1de rounded to the nearest tenth, what is the value of x?
(1) d=4 (2) e=8 CONCEPT: TO round off a number at any place we only need to know the next place digit i.e. to round off tenth we need Hundredth, To round off Hundredth we need only Thousandth digit and so on...
If next place is 0 to 4 then the digit to be rounded off remains same If next place is 5 to 9 then the digit to be rounded offis rounded up i.e. next digitQuestion : 3.1de rounded to the nearest tenth=?i.e. we only need to know the value of d Statement 1: d=4SUFFICIENT Statement 2: e=8NOT SUFFICIENT Answer: option A
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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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19 Nov 2016, 00:26
Nice Question Here decimal=3.1de rounding x to nearest tenths we will get either => 3.1 for d=0,1,2,3,4 OR 3.2 fro d=5,6,7,8,9 Hence we need the value of d here Statement 1 => sufficient => x=3.1 Statement 2 => no clue of d => not sufficient Hence A
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Re: In the decimal 3.1de, d and e each represent a digit. If x [#permalink]
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