GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 16 Oct 2019, 08:25

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Show Tags

Updated on: 21 Jan 2019, 02:44
2
3
00:00

Difficulty:

75% (hard)

Question Stats:

70% (01:39) correct 30% (02:25) wrong based on 72 sessions

HideShow timer Statistics

The price of a pastry when made fresh was $P.Each hour after the first hour the price decreased by 20%.If Lampard bought the pastry when it was just made whereas his sister bought the pastry after 3 hours, then the price paid by Lampard’s sister was what percent less than that paid by Lampard? A. 33.33% B. 40% C. 44% D. 48.8% E. 51.2 % Originally posted by DHAR on 01 Aug 2017, 08:16. Last edited by Gladiator59 on 21 Jan 2019, 02:44, edited 4 times in total. Updated OA. Senior SC Moderator Joined: 22 May 2016 Posts: 3543 Re: The price of a pastry when made fresh was$P.Each hour after the first  [#permalink]

Show Tags

01 Aug 2017, 19:17
2
DH99 wrote:
The price of a pastry when made fresh was $P.Each hour after the first hour the price decreased by 20%.If Lampard bought the pastry when it was just made whereas his sister bought the pastry after 3 hours, then the price paid by Lampard’s sister was what percent less than that paid by Julie? A. 33.33% B. 40% C. 44% D. 48.8% E. 51.2 % Who is Julie?! Sorry, couldn't resist. Definitely studying too hard. They need a cross-eyed emoji. Pastry price decreases by 20 percent for each hour after it is made. Call initial price P. Decrease of 20 percent = 1 - .20 = .80 Fresh out of oven = P 1 hour later = .80P 2 hours later = .64P (.80P * .80) 3 hours later = .512P (.64P * .80) Lampard bought a pastry fresh and paid P. His sister bought a pastry three hours later. She paid .512P Price paid by Lampard’s sister was what percent less than that paid by Lampard? Percent change = $$\frac{change}{original}$$ * 100 Change is P - .512P = .488P $$\frac{.488P}{1P}$$ = .488 * 100, or 48.8% less Answer D I usually plug in values but it got to be a mess. DH99 , you're working hard at posting all these questions. Kudos deserved and given. _________________ SC Butler has resumed! Get two SC questions to practice, whose links you can find by date, here. Choose life. Manager Joined: 15 Dec 2015 Posts: 114 GMAT 1: 680 Q49 V34 GPA: 4 WE: Information Technology (Computer Software) Re: The price of a pastry when made fresh was$P.Each hour after the first  [#permalink]

Show Tags

01 Aug 2017, 20:25
genxer123 wrote:
DH99 wrote:
The price of a pastry when made fresh was $P.Each hour after the first hour the price decreased by 20%.If Lampard bought the pastry when it was just made whereas his sister bought the pastry after 3 hours, then the price paid by Lampard’s sister was what percent less than that paid by Julie? A. 33.33% B. 40% C. 44% D. 48.8% E. 51.2 % Who is Julie?! Sorry, couldn't resist. Definitely studying too hard. They need a cross-eyed emoji. Pastry price decreases by 20 percent for each hour after it is made. Call initial price P. Decrease of 20 percent = 1 - .20 = .80 Fresh out of oven = P 1 hour later = .80P 2 hours later = .64P (.80P * .80) 3 hours later = .512P (.64P * .80) Lampard bought a pastry fresh and paid P. His sister bought a pastry three hours later. She paid .512P Price paid by Lampard’s sister was what percent less than that paid by Lampard? Percent change = $$\frac{change}{original}$$ * 100 Change is P - .512P = .488P $$\frac{.488P}{1P}$$ = .488 * 100, or 48.8% less Answer D I usually plug in values but it got to be a mess. DH99 , you're working hard at posting all these questions. Kudos deserved and given. Thank you,I will recheck the question and correct Julie.I was trying to plug in numbers as well but I got 44%. Posted from my mobile device Manager Joined: 15 Dec 2015 Posts: 114 GMAT 1: 680 Q49 V34 GPA: 4 WE: Information Technology (Computer Software) Re: The price of a pastry when made fresh was$P.Each hour after the first  [#permalink]

Show Tags

01 Aug 2017, 20:27
DH99 wrote:
genxer123 wrote:
DH99 wrote:
The price of a pastry when made fresh was $P.Each hour after the first hour the price decreased by 20%.If Lampard bought the pastry when it was just made whereas his sister bought the pastry after 3 hours, then the price paid by Lampard’s sister was what percent less than that paid by Julie? A. 33.33% B. 40% C. 44% D. 48.8% E. 51.2 % Who is Julie?! Sorry, couldn't resist. Definitely studying too hard. They need a cross-eyed emoji. Pastry price decreases by 20 percent for each hour after it is made. Call initial price P. Decrease of 20 percent = 1 - .20 = .80 Fresh out of oven = P 1 hour later = .80P 2 hours later = .64P (.80P * .80) 3 hours later = .512P (.64P * .80) Lampard bought a pastry fresh and paid P. His sister bought a pastry three hours later. She paid .512P Price paid by Lampard’s sister was what percent less than that paid by Lampard? Percent change = $$\frac{change}{original}$$ * 100 Change is P - .512P = .488P $$\frac{.488P}{1P}$$ = .488 * 100, or 48.8% less Answer D I usually plug in values but it got to be a mess. DH99 , you're working hard at posting all these questions. Kudos deserved and given. Thank you,Edited Julie to Lampard.I was trying to plug in numbers as well but I got 44%. Posted from my mobile device Posted from my mobile device Posted from my mobile device Manager Joined: 15 Dec 2015 Posts: 114 GMAT 1: 680 Q49 V34 GPA: 4 WE: Information Technology (Computer Software) Re: The price of a pastry when made fresh was$P.Each hour after the first  [#permalink]

Show Tags

01 Aug 2017, 22:11
1
genxer123 wrote:
DH99 wrote:
The price of a pastry when made fresh was $P.Each hour after the first hour the price decreased by 20%.If Lampard bought the pastry when it was just made whereas his sister bought the pastry after 3 hours, then the price paid by Lampard’s sister was what percent less than that paid by Julie? A. 33.33% B. 40% C. 44% D. 48.8% E. 51.2 % Who is Julie?! Sorry, couldn't resist. Definitely studying too hard. They need a cross-eyed emoji. Pastry price decreases by 20 percent for each hour after it is made. Call initial price P. Decrease of 20 percent = 1 - .20 = .80 Fresh out of oven = P 1 hour later = .80P 2 hours later = .64P (.80P * .80) 3 hours later = .512P (.64P * .80) Lampard bought a pastry fresh and paid P. His sister bought a pastry three hours later. She paid .512P Price paid by Lampard’s sister was what percent less than that paid by Lampard? Percent change = $$\frac{change}{original}$$ * 100 Change is P - .512P = .488P $$\frac{.488P}{1P}$$ = .488 * 100, or 48.8% less Answer D Hi, genxer123: It's given Each hour after the first hour the price decreased by 20%.So, why it will not be: Say when we take p=100. Fresh out of oven = P =100 1 hour later = 100 (same since Each hour after the first hour) 2 hours later = 80 3 hours later = 64 Senior SC Moderator Joined: 22 May 2016 Posts: 3543 Re: The price of a pastry when made fresh was$P.Each hour after the first  [#permalink]

Show Tags

02 Aug 2017, 11:20
1
1
DH99 wrote:
DH99 wrote:
The price of a pastry when made fresh was $P.Each hour after the first hour the price decreased by 20%.If Lampard bought the pastry when it was just made whereas his sister bought the pastry after 3 hours, then the price paid by Lampard’s sister was what percent less than that paid by Julie? A. 33.33% B. 40% C. 44% D. 48.8% E. 51.2 % genxer123 wrote: Pastry price decreases by 20 percent for each hour after it is made. Call initial price P. Decrease of 20 percent = 1 - .20 = .80 Fresh out of oven = P 1 hour later = .80P 2 hours later = .64P (.80P * .80) 3 hours later = .512P (.64P * .80) Lampard bought a pastry fresh and paid P. His sister bought a pastry three hours later. She paid .512P Price paid by Lampard’s sister was what percent less than that paid by Lampard? Percent change = $$\frac{change}{original}$$ * 100 Change is P - .512P = .488P $$\frac{.488P}{1P}$$ = .488 * 100, or 48.8% less Answer D DH99 wrote: Hi, genxer123: It's given Each hour after the first hour the price decreased by 20%.So, why it will not be: Say when we take p=100. Fresh out of oven = P =100 1 hour later = 100 (same since Each hour after the first hour) 2 hours later = 80 3 hours later = 64 DH99 , good question. I agree that the highlighted phrase is confusing. After plugging in numbers as you did, the "percent less than" was $$\frac{(100 - 64)}{100}$$ * 100 = 36 percent less. That's not an option in the answer choices. Conclusion: I was wrong to think, "One hour passed, and AFTER THAT, the price decreased every hour, so first decrease hits at the end of the second hour." So I thought about when "after the first hour" could begin to toll. When does "the first hour" start and end? Say that out of the oven time is 0:00. Clock begins to run. 60 minutes pass = one hour. Now we are at 1:00. Think of a round clock face, put one tick mark at 0:00, and another at 1:00. At the end of that one hour, we are "at" the tick mark that signals the end of the first hour; at 1:00 we are, time wise, at "after the first hour. . ." and "the price decrease[s] by 20%." The confusion comes from "each" at the beginning of the sentence. "Each hour after the first hour" seems to suggest that the first hour is not in the group of hours where a decrease happens. The first hour IS in that group. If I were editing for clarity, I would rewrite: "For every hour after the pastry is taken fresh from the oven, the price decreased by 20 percent." That said, although I dislike the phrase thoroughly, its obscure quality nonetheless has a meaning that is defensible. Barely, but defensible. If the answer choices had contained 36 percent, I'd argue otherwise. Does that help? If not, keep asking about what you don't understand. _________________ SC Butler has resumed! Get two SC questions to practice, whose links you can find by date, here. Choose life. Manager Joined: 15 Dec 2015 Posts: 114 GMAT 1: 680 Q49 V34 GPA: 4 WE: Information Technology (Computer Software) Re: The price of a pastry when made fresh was$P.Each hour after the first  [#permalink]

Show Tags

02 Aug 2017, 11:31
genxer123

Thanks for the clarification.However, if the question is kept as it is and 36 is one of the options the answer would have been 36.right?
Senior SC Moderator
Joined: 22 May 2016
Posts: 3543

Show Tags

17 Apr 2018, 06:06
DHAR wrote:
The price of a pastry when made fresh was $P.Each hour after the first hour the price decreased by 20%.If Lampard bought the pastry when it was just made whereas his sister bought the pastry after 3 hours, then the price paid by Lampard’s sister was what percent less than that paid by Lampard? A. 33.33% B. 40% C. 44% D. 48.8% E. 51.2 % I think OA should be changed. Answer seems to be D. _________________ - Stne Senior PS Moderator Status: It always seems impossible until it's done. Joined: 16 Sep 2016 Posts: 737 GMAT 1: 740 Q50 V40 GMAT 2: 770 Q51 V42 Re: The price of a pastry when made fresh was$P.Each hour after the first  [#permalink]

Show Tags

21 Jan 2019, 02:44
1
Update OA to D. Thanks generis Stne and others who pointed out.

Posted from my mobile device
_________________
Regards,

“Do. Or do not. There is no try.” - Yoda (The Empire Strikes Back)