Oct 19 07:00 AM PDT  09:00 AM PDT Does GMAT RC seem like an uphill battle? eGMAT is conducting a free webinar to help you learn reading strategies that can enable you to solve 700+ level RC questions with at least 90% accuracy in less than 10 days. Sat., Oct 19th at 7 am PDT Oct 18 08:00 AM PDT  09:00 AM PDT Learn an intuitive, systematic approach that will maximize your success on Fillintheblank GMAT CR Questions. Oct 20 07:00 AM PDT  09:00 AM PDT Get personalized insights on how to achieve your Target Quant Score. Oct 22 08:00 PM PDT  09:00 PM PDT On Demand for $79. For a score of 4951 (from current actual score of 40+) AllInOne Standard & 700+ Level Questions (150 questions) Oct 23 08:00 AM PDT  09:00 AM PDT Join an exclusive interview with the people behind the test. If you're taking the GMAT, this is a webinar you cannot afford to miss!
Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 58453

Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
21 Apr 2017, 07:44
Question Stats:
59% (02:58) correct 41% (02:53) wrong based on 180 sessions
HideShow timer Statistics
Rachel needs to type up her 1950word paper by its 5 pm deadline. If she starts at least two hours in advance, her typing speed will be a constant 20 words per minute, but for every two minutes beyond 3 pm that she waits before starting, her constant typing speed will increase by one word per minute. What is the latest time at which Rachel can begin typing in order to finish her paper by the deadline? A. 2:50 pm B. 3:23 pm C. 3:30 pm D. 4:30 pm E. 4:42 pm
Official Answer and Stats are available only to registered users. Register/ Login.
_________________



Senior Manager
Joined: 24 Apr 2016
Posts: 323

Re: Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
21 Apr 2017, 10:40
Her constant typing speed at 3PM = 20 words/minute
For every two minute delay after 3 PM constant typing speed increased by 1 word
So if she starts at 3:02 PM her speed will be 21 words/minute
So if she starts at 3:22 PM her speed will be 31 words/minute
So if she starts at 3:30 PM her speed will be 35 words/minute
So if she starts at 4:00 PM her speed will be 50 words/minute
So if she starts at 4:30 PM her speed will be 65 words/minute
So if she starts at 4:42 PM her speed will be 70 words/minute
Going by options,
Option E: if she starts at 4:42 PM with a constant speed of 70 words/minute, she will have 18 minutes to complete. So 1950/70 should be less than equal to 18. But 1950/70 comes to 27.9 minutes. So Option E is ruled out.
Option D: if she starts at 4:30 PM with a constant speed of 65 words/minute, she will have 30 minutes to complete. So 1950/65 should be less than equal to 30. 1950/65 comes to 30 minutes. So Option D is the correct choice.
Answer D. 4:30 pm



VP
Joined: 07 Dec 2014
Posts: 1222

Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
21 Apr 2017, 16:24
Bunuel wrote: Rachel needs to type up her 1950word paper by its 5 pm deadline. If she starts at least two hours in advance, her typing speed will be a constant 20 words per minute, but for every two minutes beyond 3 pm that she waits before starting, her constant typing speed will increase by one word per minute. What is the latest time at which Rachel can begin typing in order to finish her paper by the deadline?
A. 2:50 pm B. 3:23 pm C. 3:30 pm D. 4:30 pm E. 4:42 pm let m=minimum minutes before 5pm needed by Rachel m[20+1/2*(120m)]=1950 m^2160m+3900=0 (m30)(m130)=0 m=30 minutes 5pm30 minutes=4:30pm D



Senior SC Moderator
Joined: 14 Nov 2016
Posts: 1348
Location: Malaysia

Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
06 May 2017, 18:16
Bunuel wrote: Rachel needs to type up her 1950word paper by its 5 pm deadline. If she starts at least two hours in advance, her typing speed will be a constant 20 words per minute, but for every two minutes beyond 3 pm that she waits before starting, her constant typing speed will increase by one word per minute. What is the latest time at which Rachel can begin typing in order to finish her paper by the deadline?
A. 2:50 pm B. 3:23 pm C. 3:30 pm D. 4:30 pm E. 4:42 pm OFFICIAL EXPLANATION Backsolving is a good option for this problem. It is best to begin by checking the last time and then work backwards, since we want the latest time at which Rachel can start. Starting at 4:42 pm would give Rachel 18 minutes to write at a rate of \(20+\frac{102}{2}=71\) words per minute. This is approximately 20∗70=1400 words, which is well short of the 1950 necessary to complete the assignment. Starting at 4:30 pm would give Rachel 30 minutes to write at a rate of \(20+\frac{90}{2}=65\) words per minute. This is 30∗65=1950 words. Perfect. This must be the correct answer. D. Could someone help to explain the rate in this problem? constant typing speed will increase by one word per minute.
_________________
"Be challenged at EVERY MOMENT."“Strength doesn’t come from what you can do. It comes from overcoming the things you once thought you couldn’t.”"Each stage of the journey is crucial to attaining new heights of knowledge."Rules for posting in verbal forum  Please DO NOT post short answer in your post! Advanced Search : https://gmatclub.com/forum/advancedsearch/



EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 15271
Location: United States (CA)

Re: Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
12 Jan 2018, 14:20
Hi All, This question can be solved by TESTing THE ANSWERS. This is essentially a rate question, but the rate (and the time spent at that rate) changes depending on what time Rachel begins typing. Based on the information in the prompt, we know that if Rachel begins typing at 3pm, then she can type for up to 2 hours (re: 120 minutes) at 20 words/minute. Thus, she could type (20)(120) = 2400 total words during that time... and that would be enough time to complete the 1950 word paper. For every TWO minutes past 3pm that she gets started, her typing speed will increase by 1 word/minute (BUT keep in mind that her available typing time will decrease by 2 minutes). For example, if she begins at 3:02pm, then she can type of up to 118 minutes at 21 words per minute, which would total (21)(118) = 2478 total words. We're asked for the LATEST that she could begin typing and still complete the paper on time. Let's TEST Answer E: 4:42pm > 18 minutes at 71 words/minute = 1,278 total words. That is NOT enough. Eliminate Answer E. Let's TEST Answer D: 4:30pm > 30 minutes at 65 words/minute = 1,950 total words. That IS exactly enough, so this must be the answer. Final Answer: GMAT assassins aren't born, they're made, Rich
_________________
Contact Rich at: Rich.C@empowergmat.comThe Course Used By GMAT Club Moderators To Earn 750+ souvik101990 Score: 760 Q50 V42 ★★★★★ ENGRTOMBA2018 Score: 750 Q49 V44 ★★★★★



Intern
Joined: 28 Mar 2017
Posts: 4

Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
13 Jan 2018, 02:18
Hi everyone, In my opinion, to make an equation is the easiest way to solve this problem. x  additional speed for every 2 minutes, after 3 pm (1202x)  time left for writing (20+x)  speed The equation is the following: (1202x)(20+x)=1950 x^240x+450=0 x=45 Meaning that she can start writing 45*2=90 min after 3pm, or, in other words, 4:30pm. ANS: DPlease, kudos



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8104
Location: United States (CA)

Re: Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
06 Jun 2019, 18:02
Bunuel wrote: Rachel needs to type up her 1950word paper by its 5 pm deadline. If she starts at least two hours in advance, her typing speed will be a constant 20 words per minute, but for every two minutes beyond 3 pm that she waits before starting, her constant typing speed will increase by one word per minute. What is the latest time at which Rachel can begin typing in order to finish her paper by the deadline?
A. 2:50 pm B. 3:23 pm C. 3:30 pm D. 4:30 pm E. 4:42 pm Let’s analyze the answer choices (in reverse order). If Rachel starts at 4:42 pm (and notice that 4:42 pm is 102 minutes after 3 pm), she has to type 20 + 102/2 = 20 + 51 = 71 words per minute (wpm). Since she has only 18 minutes left until 5 pm, she can type 18 x 71 = 1278 words, which means she will miss the deadline of 5 pm. If Rachel starts at 4:30 pm (and notice that 4:30 pm is 90 minutes after 3 pm), she has to type 20 + 90/2 = 20 + 45 = 65 words per minute (wpm). Since she has only 30 minutes left until 5 pm, she can type 30 x 65 = 1950 words, which means she will just make the deadline of 5 pm. Answer: D
_________________
5star rated online GMAT quant self study course See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews If you find one of my posts helpful, please take a moment to click on the "Kudos" button.



Manager
Joined: 08 Apr 2019
Posts: 148
Location: India
GPA: 4

Re: Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
28 Jun 2019, 19:39
ScottTargetTestPrep wrote: Bunuel wrote: Rachel needs to type up her 1950word paper by its 5 pm deadline. If she starts at least two hours in advance, her typing speed will be a constant 20 words per minute, but for every two minutes beyond 3 pm that she waits before starting, her constant typing speed will increase by one word per minute. What is the latest time at which Rachel can begin typing in order to finish her paper by the deadline?
A. 2:50 pm B. 3:23 pm C. 3:30 pm D. 4:30 pm E. 4:42 pm Let’s analyze the answer choices (in reverse order). If Rachel starts at 4:42 pm (and notice that 4:42 pm is 102 minutes after 3 pm), she has to type 20 + 102/2 = 20 + 51 = 71 words per minute (wpm). Since she has only 18 minutes left until 5 pm, she can type 18 x 71 = 1278 words, which means she will miss the deadline of 5 pm. If Rachel starts at 4:30 pm (and notice that 4:30 pm is 90 minutes after 3 pm), she has to type 20 + 90/2 = 20 + 45 = 65 words per minute (wpm). Since she has only 30 minutes left until 5 pm, she can type 30 x 65 = 1950 words, which means she will just make the deadline of 5 pm. Answer: D ScottTargetTestPrep EMPOWERgmatRichC have you assumed that while writing her speed remains constant? What I understood from the question stem was that her speed increases by 1 word / min. every 2 mins. after 3 PM, so let's say she's started writing at 4:30 PM, assuming her speed would be some 20 + a, won't her speed increase to 20 + a + 1 at 4:32 PM and then 20 + a + 2 at 4:34 PM nd 20 + a + 3 at 4:36 PM and so on? Please help!



EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 15271
Location: United States (CA)

Re: Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
29 Jun 2019, 15:07
Hi RJ7X0DefiningMyX, The prompt refers to her "constant typing speed" once she STARTS typing. There's nothing in the wording that describes how she would get 'faster' over time (as she keeps typing), so that's a misinterpretation on your part. GMAT assassins aren't born, they're made, Rich
_________________
Contact Rich at: Rich.C@empowergmat.comThe Course Used By GMAT Club Moderators To Earn 750+ souvik101990 Score: 760 Q50 V42 ★★★★★ ENGRTOMBA2018 Score: 750 Q49 V44 ★★★★★



Manager
Joined: 09 Nov 2015
Posts: 134

Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
Updated on: 04 Jul 2019, 01:23
arshak90This approach is the quickest and simplest and one that I too adopted. However, although your answer is the right one, there is a mistake in your calculations: The equation [(1202x)(20+x)=1950] does NOT simplify to: [x^2  40x +450 = 0]. Following is the detailed breakdown of the calculations: (1202x)(20+x)=1950....> 2400+120x40x2x^2=1950...> 2x^280x450=0...> x^240x225=0...> x^245x+5x225...> x(x45)+5(x45)=0...> (x45)(x+5)=0...> x=45 Therefore, the latest that Rachel can start is 90(45*2) minutes after 3 pm i.e. at 4:30 pm. ANS: D
Originally posted by effatara on 01 Jul 2019, 23:30.
Last edited by effatara on 04 Jul 2019, 01:23, edited 1 time in total.



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8104
Location: United States (CA)

Re: Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
Show Tags
02 Jul 2019, 18:45
RJ7X0DefiningMyX wrote: ScottTargetTestPrep wrote: Bunuel wrote: Rachel needs to type up her 1950word paper by its 5 pm deadline. If she starts at least two hours in advance, her typing speed will be a constant 20 words per minute, but for every two minutes beyond 3 pm that she waits before starting, her constant typing speed will increase by one word per minute. What is the latest time at which Rachel can begin typing in order to finish her paper by the deadline?
A. 2:50 pm B. 3:23 pm C. 3:30 pm D. 4:30 pm E. 4:42 pm Let’s analyze the answer choices (in reverse order). If Rachel starts at 4:42 pm (and notice that 4:42 pm is 102 minutes after 3 pm), she has to type 20 + 102/2 = 20 + 51 = 71 words per minute (wpm). Since she has only 18 minutes left until 5 pm, she can type 18 x 71 = 1278 words, which means she will miss the deadline of 5 pm. If Rachel starts at 4:30 pm (and notice that 4:30 pm is 90 minutes after 3 pm), she has to type 20 + 90/2 = 20 + 45 = 65 words per minute (wpm). Since she has only 30 minutes left until 5 pm, she can type 30 x 65 = 1950 words, which means she will just make the deadline of 5 pm. Answer: D ScottTargetTestPrep EMPOWERgmatRichC have you assumed that while writing her speed remains constant? What I understood from the question stem was that her speed increases by 1 word / min. every 2 mins. after 3 PM, so let's say she's started writing at 4:30 PM, assuming her speed would be some 20 + a, won't her speed increase to 20 + a + 1 at 4:32 PM and then 20 + a + 2 at 4:34 PM nd 20 + a + 3 at 4:36 PM and so on? Please help! Actually, according to the question stem, Rachel’s typing speed does not increase every minute; that’s the reason the question is emphasizing that her typing speed is constant. Depending on how much time she has until the deadline, she determines a typing speed and types at that constant speed until she finishes. That’s why we take her writing speed to be constant once she begins typing.
_________________
5star rated online GMAT quant self study course See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews If you find one of my posts helpful, please take a moment to click on the "Kudos" button.




Re: Rachel needs to type up her 1950word paper by its 5 pm deadline. If
[#permalink]
02 Jul 2019, 18:45






