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If t denotes the thousandths digit in the decimal [#permalink]
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03 Sep 2012, 06:04
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Re: If t denotes the thousandths digit in the decimal [#permalink]
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03 Sep 2012, 06:04
SOLUTIONRounding 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. For more check Number Theory chapter of Math Book: mathnumbertheory88376.htmlBACK TO THE ORIGINAL QUESTION: d = 0.43t7 If t denotes the thousandths digit in the decimal representation of d above, what digit is t?(1) If d were rounded to the nearest hundredth, the result would be 0.44. Just says that \(t\geq{5}\). Not sufficient. (2) If d were rounded to the nearest thousandth, the result would be 0.436. Since 7 is more than 5, then \(t\) was rounded up to become 6, hence \(t=5\). Sufficient. Answer: B.
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Re: If t denotes the thousandths digit in the decimal [#permalink]
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03 Sep 2012, 06:27
Statement (1): d is rounded up. So the thousandth digit can take the values 5, 6, 7, 8, 9. > not sufficient Statement (2): d is again rounded up, because the tenthousandths digit is 7. Therefore, the thousands digit is 5. > sufficient
Answer B, Statement (2) is sufficient, Statement (1) is not sufficient.



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Re: If t denotes the thousandths digit in the decimal [#permalink]
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07 Sep 2012, 05:29
SOLUTIONRounding 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. For more check Number Theory chapter of Math Book: mathnumbertheory88376.htmlBACK TO THE ORIGINAL QUESTION: d = 0.43t7 If t denotes the thousandths digit in the decimal representation of d above, what digit is t?(1) If d were rounded to the nearest hundredth, the result would be 0.44. Just says that \(t\geq{5}\). Not sufficient. (2) If d were rounded to the nearest thousandth, the result would be 0.436. Since 7 is more than 5, then \(t\) was rounded up to become 6, hence \(t=5\). Sufficient. Answer: B. Kudos points given to everyone with correct solution. Let me know if I missed someone.
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Re: If t denotes the thousandths digit in the decimal [#permalink]
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26 Dec 2014, 09:22
Not sure if B is correct.
In GMAT can we assume that rounding means rounding up if >=0.5 and rounding down if <0.5? Could also be always rounding up or down (no matter what digit)



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Re: If t denotes the thousandths digit in the decimal [#permalink]
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26 Dec 2014, 09:25
noshtafoyza wrote: Not sure if B is correct.
In GMAT can we assume that rounding means rounding up if >=0.5 and rounding down if <0.5? Could also be always rounding up or down (no matter what digit) This is a question from Official Guide and the Official Answer is B. Rounding rules are given in the second post: iftdenotesthethousandthsdigitinthedecimal138297.html#p1119527Rounding 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.
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Re: If t denotes the thousandths digit in the decimal [#permalink]
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19 May 2015, 15:19
Bunuel wrote: SOLUTIONRounding 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. For more check Number Theory chapter of Math Book: mathnumbertheory88376.htmlBACK TO THE ORIGINAL QUESTION: d = 0.43t7 If t denotes the thousandths digit in the decimal representation of d above, what digit is t?(1) If d were rounded to the nearest hundredth, the result would be 0.44. Just says that \(t\geq{5}\). Not sufficient. (2) If d were rounded to the nearest thousandth, the result would be 0.436. Since 7 is more than 5, then \(t\) was rounded up to become 6, hence \(t=5\). Sufficient. Answer: B. If t = 4 > d = 0.4347 = 0.435 = 0.44 => t >= 4 not t >= 5 Am I right?



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Re: If t denotes the thousandths digit in the decimal [#permalink]
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20 May 2015, 02:41
avgroh wrote: Bunuel wrote: SOLUTIONRounding 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. For more check Number Theory chapter of Math Book: mathnumbertheory88376.htmlBACK TO THE ORIGINAL QUESTION: d = 0.43t7 If t denotes the thousandths digit in the decimal representation of d above, what digit is t?(1) If d were rounded to the nearest hundredth, the result would be 0.44. Just says that \(t\geq{5}\). Not sufficient. (2) If d were rounded to the nearest thousandth, the result would be 0.436. Since 7 is more than 5, then \(t\) was rounded up to become 6, hence \(t=5\). Sufficient. Answer: B. If t = 4 > d = 0.4347 = 0.435 = 0.44 => t >= 4 not t >= 5 Am I right? No. When rounding to the tenth you look at only the hundredth digit, when rounding to the hundredth you look at only the thousandth digit, etc. Please reread rounding rules given above.
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Re: If t denotes the thousandths digit in the decimal [#permalink]
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20 May 2015, 03:04
avgroh wrote: Bunuel wrote: SOLUTIONRounding 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. For more check Number Theory chapter of Math Book: mathnumbertheory88376.htmlBACK TO THE ORIGINAL QUESTION: d = 0.43t7 If t denotes the thousandths digit in the decimal representation of d above, what digit is t?(1) If d were rounded to the nearest hundredth, the result would be 0.44. Just says that \(t\geq{5}\). Not sufficient. (2) If d were rounded to the nearest thousandth, the result would be 0.436. Since 7 is more than 5, then \(t\) was rounded up to become 6, hence \(t=5\). Sufficient. Answer: B. If t = 4 > d = 0.4347 = 0.435 = 0.44 => t >= 4 not t >= 5 Am I right? Hi avgroh, StI talks about rounding off to the nearest hundredth. Since the number is 0.43t7 and 3 is at the hundredths place, for rounding off to the nearest hundredth we will only consider the value of the digit next to it. As 0.43t7 has been rounded off to 0.44 that would mean t =>5. Rounding off from the right most digit is not the right way to go about rounding off process. Think of it this way: Consider the number 1.448 which is to be rounded off to the nearest tenths. If you start from the right most digit you would round off it as 1.448 > 1.45 > 1.5. But 1.448 is nearer to 1.4 than to 1.5, right? Hence the only thing that should matter is the next digit to which a number is to be rounded off. Hence for the number 1.448, to round it off to the nearest tenths, the digit next to tenths place i.e. 4 should matter and it should be rounded off to 1.4. Hope it's clear Regards Harsh
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Re: If t denotes the thousandths digit in the decimal [#permalink]
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09 Aug 2016, 13:41
Quote: d = 0.43t7 If t denotes the thousandths digit in the decimal representation of d above, what digit is t?
(1) If d were rounded to the nearest hundredth, the result would be 0.44. (2) If d were rounded to the nearest thousandth, the result would be 0.436. We are given that t denotes the thousandths digit of 0.43t7. We need to determine the value of t. Statement One Alone:If d were rounded to the nearest hundredth, the result would be 0.44. Using the information in statement one, t could be different values. For example, t could be 5 (so that d would be 0.4357) or t could be 6 (so that d would be 0.4367). Similarly, t could also be 7, 8, or 9. Notice in any of these cases, d rounds up to 0.44. Thus, statement one is not enough information to answer the question. We can eliminate answer choices A and D. Statement Two Alone:If d were rounded to the nearest thousandth, the result would be 0.436. Using the information from statement two, d must be 0.4357. Because of the “7” in the tenthousandths digit, we see that 0.43t7 will only round up to 0.436. Thus, t can only be the value 5. Any other value of t will not round d to 0.436 when rounded to the nearest thousandth. Statement two is sufficient to answer the question. The answer is B.
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