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Whenever martin has a restaurant bill with an amount between
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12 Feb 2011, 13:48
Question Stats:
67% (02:24) correct 33% (02:23) wrong based on 956 sessions
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Whenever martin has a restaurant bill with an amount between $10 and $99, he calculates the dollar amount of the tip as 2times the tens digit of the amount of his bill.If the amount of the Martin's most recent restaurant bill was between $10 and $99, was the tip calculated by the martin on this bill greater than 15 percent of the amount of the bill? (1) The amount of the bill was between $15 and $50 (2) The tip calculated by the martin was $8 1) as bill amount is between $15 and $50 tens digit can be any digit from 1,2,3,4
not sufficient
2) tip is 8 let y is the tens digit 2(y) = 8 y = 4 not sufficient
from 1 and 2
for any value of tens digit from 1 to 4 inclusive
and y=4
we can conclude that calculated tip ill be greater than the 15% of amount of bill
C
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Re: Whenever martin has a restaurant bill with an amount between
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12 Feb 2011, 14:21
GMATD11 wrote: whenever martin has a restaurant bill with an amount between $10 and $99, he calculates the dollar amount of the tip as 2times the tens digit of the amount of his bill. If the amount of the Martin's most recent restaurant bill was between $10 and $99, was the tip calculated by the martin on this bill greater than 15 percent of the amount of the bill?
1) The amount of the bill was between $15 and $50 2) The tip calculated by the martin was $8 C is not correct. You can solve this question algebraically but I think simple analysis would be better. (1) The amount of the bill was between $15 and $50 > 15<bill<50. Now if the bill was 20$ then the tip would be 2*2=$4 (2 times tens digit) so more than 0.15*20=$3 (15% of the bill) but if the bill was 29$ then the tip would still be 2*2=$4 but in this case less than 0.15*29=~$4.5. Not sufficient. (2) The tip calculated by the martin was $8 > Tip=$8 means that: 40<=bill<50 (so that the tens digit of the bill to be 4). Now, even if the bill was exactly $50 (uppert limit), 15% of it would be 0.15*50=$7.5 and it's still less than $8. So the answer to the question is YES: the tip (8$) was greater than 15% of the bill. Sufficient. Answer: B. Similar question: sallysbillgreaterthan25oftheamount108351.html
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Re: Whenever martin has a restaurant bill with an amount between
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12 Feb 2011, 15:14
yes, it has to be B. since the 15% of 50 is 7.5, and if the tip is 8, then the tip value between 40 to 50 will always be more than 7.5
where as for 1 the value can be less than 15% to more than 15%, depending if the amount is for example between 15 to 19, vs between 25 to 29



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Re: Whenever martin has a restaurant bill with an amount between
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31 May 2013, 05:43
Bumping for review and further discussion*. Get a kudos point for an alternative solution! *New project from GMAT Club!!! Check HERE
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Re: Whenever martin has a restaurant bill with an amount between
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17 Oct 2013, 07:01
Bunuel wrote: GMATD11 wrote: whenever martin has a restaurant bill with an amount between $10 and $99, he calculates the dollar amount of the tip as 2times the tens digit of the amount of his bill. If the amount of the Martin's most recent restaurant bill was between $10 and $99, was the tip calculated by the martin on this bill greater than 15 percent of the amount of the bill?
1) The amount of the bill was between $15 and $50 2) The tip calculated by the martin was $8 C is not correct. You can solve this question algebraically but I think simple analysis would be better. (1) The amount of the bill was between $15 and $50 > 15<bill<50. Now if the bill was 20$ then the tip would be 2*2=$4 (2 times tens digit) so more than 0.15*20=$3 (15% of the bill) but if the bill was 29$ then the tip would still be 2*2=$4 but in this case less than 0.15*29=~$4.5. Not sufficient. (2) The tip calculated by the martin was $8 > Tip=$8 means that: 40<=bill<50 (so that the tens digit of the bill to be 4). Now, even if the bill was exactly $50 (uppert limit), 15% of it would be 0.15*50=$7.5 and it's still less than $8. So the answer to the question is YES: the tip (8$) was greater than 15% of the bill. Sufficient. Answer: B. Similar question: sallysbillgreaterthan25oftheamount108351.htmlHi Bunuel, for this question. In the first statement, how do you know what amount for the bill to choose in order to increase your odds of having a yes/no answer. Do you tipically look for a lower/middle or upper range? Thanks Cheers J



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Re: Whenever martin has a restaurant bill with an amount between
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17 Oct 2013, 08:38
jlgdr wrote: Bunuel wrote: GMATD11 wrote: whenever martin has a restaurant bill with an amount between $10 and $99, he calculates the dollar amount of the tip as 2times the tens digit of the amount of his bill. If the amount of the Martin's most recent restaurant bill was between $10 and $99, was the tip calculated by the martin on this bill greater than 15 percent of the amount of the bill?
1) The amount of the bill was between $15 and $50 2) The tip calculated by the martin was $8 C is not correct. You can solve this question algebraically but I think simple analysis would be better. (1) The amount of the bill was between $15 and $50 > 15<bill<50. Now if the bill was 20$ then the tip would be 2*2=$4 (2 times tens digit) so more than 0.15*20=$3 (15% of the bill) but if the bill was 29$ then the tip would still be 2*2=$4 but in this case less than 0.15*29=~$4.5. Not sufficient. (2) The tip calculated by the martin was $8 > Tip=$8 means that: 40<=bill<50 (so that the tens digit of the bill to be 4). Now, even if the bill was exactly $50 (uppert limit), 15% of it would be 0.15*50=$7.5 and it's still less than $8. So the answer to the question is YES: the tip (8$) was greater than 15% of the bill. Sufficient. Answer: B. Similar question: sallysbillgreaterthan25oftheamount108351.htmlHi Bunuel, for this question. In the first statement, how do you know what amount for the bill to choose in order to increase your odds of having a yes/no answer. Do you tipically look for a lower/middle or upper range? Thanks Cheers J Well, it depends on the question but to test extreme values might be a good thing to do. For this question, as the tip is tied to the tens digit of the bill, then I chose two extreme amounts which have the same tens digit so generate the same tip (20 and 29).
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Re: Whenever martin has a restaurant bill with an amount between
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18 May 2014, 10:59
Bill is XY and the tip is 2X
Question is :
Is 2x/(10x+Y) > 15/100 ?
Or if we simplfy this expression: Is 10X>3Y
Remember Y can be between 09 so 3y Can be 27 MAX ( 3x9)
So if 10X>27 X needs to be greater than 2 Exclamation
Statement 1) 1<x<5 INSUF Statement 2) tip = 8, so X = 4 which is greater than 2 SUF
Hence, B



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Re: Whenever martin has a restaurant bill with an amount between
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05 Oct 2014, 00:37
Bunuel wrote: Bumping for review and further discussion*. Get a kudos point for an alternative solution! *New project from GMAT Club!!! Check HEREGiven: Let A = amount of the bill, in which 10 < A < 99 Let T = tip Let t(A) = tens digit of the amount, > T = 2*t(A) Question: T > 15%(A)? 2*t(A) > 15%(A)? 2*t(A) > \(\frac{3}{20}\)*A? \(\frac{40}{3}\) > \(\frac{A}{t(A)}\)? (1) 15 < A < 30 If A = 20, t(A) = 2 \(\frac{40}{3}\) > \(\frac{20}{2}\)? Yes If A = 29, t(A) = 2 \(\frac{40}{3}\) > \(\frac{29}{2}\)? No Hence, insufficient. (2) T = 8 8 = 2*t(A) > 4=t*(A) > Possible values for T: 41, 42,...,49 If A = 49, t(A) = 4 \(\frac{40}{3}\) > \(\frac{49}{4}\)? Yes If A = 40, t(A) = 4 \(\frac{40}{3}\) > \(\frac{40}{4}\)? Yes Hence, sufficient. Answer: B



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Re: Whenever martin has a restaurant bill with an amount between
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14 Sep 2017, 21:31
Hi Bunuel, Actually for GMAT DS problems, statements never contradict each other. However this question, Statement 1 > total paid amount is between 15 and 30 Statement 2 > total paid amount is between 40 and 49 inclusive.
So each statement gives diff bill paid amount, contradicting each other. can this be so?



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Whenever martin has a restaurant bill with an amount between
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14 Sep 2017, 21:39
hellosanthosh2k2 wrote: Hi Bunuel, Actually for GMAT DS problems, statements never contradict each other. However this question, Statement 1 > total paid amount is between 15 and 30 Statement 2 > total paid amount is between 40 and 49 inclusive.
So each statement gives diff bill paid amount, contradicting each other. can this be so? The statement do not contradict. From (1): 15 < bill < 50. From (2): 40 <= bill < 50.
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Re: Whenever martin has a restaurant bill with an amount between
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30 Mar 2019, 12:15
GMATD11 wrote: Whenever martin has a restaurant bill with an amount between $10 and $99, he calculates the dollar amount of the tip as 2times the tens digit of the amount of his bill.If the amount of the Martin's most recent restaurant bill was between $10 and $99, was the tip calculated by the martin on this bill greater than 15 percent of the amount of the bill? (1) The amount of the bill was between $15 and $50 (2) The tip calculated by the martin was $8 1) as bill amount is between $15 and $50 tens digit can be any digit from 1,2,3,4
not sufficient
2) tip is 8 let y is the tens digit 2(y) = 8 y = 4 not sufficient
from 1 and 2
for any value of tens digit from 1 to 4 inclusive
and y=4
we can conclude that calculated tip ill be greater than the 15% of amount of bill
C Similar to Q: https://gmatclub.com/forum/whenevertom ... l#p2251666Solution: Trick: Min/Max List the Ranges: Bill Range: 1119, 2129, 3139, 4149, ..., 9199 Tip Range: 1.5<x<3, 3<x<4.5, 4.5<x<6, 6<x<7.5, ..., 13.5<x<15 Actual Tip: 2, 4, 6, ..., 18 Simplify the Q Notice, tip > 15% of the bill when: 1) bill > 30 2) tip > $4 Hence the Q is asking: Is bill > 30 or tip > 4?1) 15 < bill < 50. Not sufficient since b > 30. 2) Tip = 8. Sufficient since tip > 4 Hence, answer = B.
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Re: Answers that did not make sense in OG Quant
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17 Oct 2019, 02:42
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Re: Answers that did not make sense in OG Quant
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