BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

Investment, Interest rates and formula

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 661
Joined: Tue Jul 08, 2008 12:58 pm
Location: France
Thanked: 48 times
by pepeprepa » Thu Aug 28, 2008 4:30 am
An investor purchased a share of non-dividend-paying stock for p dollars on Monday. For a certain number of days, the value of the share increased by r percent per day. After this period of constant increase, the value of the share decreased the next day by q dollars and the investor decided to sell the share at the end of that day for v dollars, which was the value of the share at that time. How many working days after the investor bought the share was the share sold, if
r= 100 * ( sqrt( (v+q)/p ) -1 ) ?
A) Two working days later.
B) Three working days later.
C) Four working days later.
D) Five working days later.
E) Six working days later
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Legendary Member
Posts: 829
Joined: Mon Jul 07, 2008 10:09 pmFollowed by: 3 members
Location: INDIA
Thanked: 84 times

Re: Investment, Interest rates and formula

by sudhir3127 » Thu Aug 28, 2008 5:01 am
pepeprepa wrote:An investor purchased a share of non-dividend-paying stock for p dollars on Monday. For a certain number of days, the value of the share increased by r percent per day. After this period of constant increase, the value of the share decreased the next day by q dollars and the investor decided to sell the share at the end of that day for v dollars, which was the value of the share at that time. How many working days after the investor bought the share was the share sold, if
r= 100 * ( sqrt( (v+q)/p ) -1 ) ?
A) Two working days later.
B) Three working days later.
C) Four working days later.
D) Five working days later.
E) Six working days later
For me its B

Assuming X days ...

i am using Compound Interest.

v = p (1+r/100)^x - q

if i solve for r i get

r=(xth root of (v +q)/p -1 )*100.......................................1

Question stem tells us that

r= 100 * ( sqrt( (v+q)/p ) -1 )...........................................2

substitute 2 in 1

we get
100 * ( ( (v+q)/p ) -1 )^1/2 = [(v +q)/p -1 )]^1/x*100

from this we know X =2

Thus the shares rose for 2 days and on the following day they fell and the investor sold in on the next day

thus its 2+ 1 days = 3

hope that helps..
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 661
Joined: Tue Jul 08, 2008 12:58 pm
Location: France
Thanked: 48 times

by pepeprepa » Thu Aug 28, 2008 5:04 am
That's it, I think there is only one way.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Junior | Next Rank: 30 Posts
Posts: 17
Joined: Mon Jan 19, 2009 12:11 am
Thanked: 3 times
GMAT Score:640

great job! still one little question though

by Edthesock » Tue Jan 20, 2009 8:15 pm
Wow... I spent so long on this. Very good job Sudhir, very impressive, especially if you did it in 2 minutes like a standard GMAT question!

I'm okay for solving x to get 2 days in the compound interest formula, but how do you know the stock was sold 1 day later?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 829
Joined: Mon Jul 07, 2008 10:09 pmFollowed by: 3 members
Location: INDIA
Thanked: 84 times

Re: great job! still one little question though

by sudhir3127 » Tue Jan 20, 2009 9:51 pm
Edthesock wrote:Wow... I spent so long on this. Very good job Sudhir, very impressive, especially if you did it in 2 minutes like a standard GMAT question!

I'm okay for solving x to get 2 days in the compound interest formula, but how do you know the stock was sold 1 day later?
Because the question says
"After this period of constant increase, the value of the share decreased the next day by q dollars and the investor decided to sell the share at the end of that day for v dollars"

this period here is 2 days
next day would be day 3.

hope this clear .. do let me know if u need any help ..
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1