• Target Test Prep
    5-Day Free Trial
    5-day free, full-access trial TTP Quant

    Available with Beat the GMAT members only code

    MORE DETAILS
    Target Test Prep
  • EMPOWERgmat Slider
    1 Hour Free
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    EMPOWERgmat Slider
  • Magoosh
    Magoosh
    Study with Magoosh GMAT prep

    Available with Beat the GMAT members only code

    MORE DETAILS
    Magoosh
  • Varsity Tutors
    Award-winning private GMAT tutoring
    Register now and save up to $200

    Available with Beat the GMAT members only code

    MORE DETAILS
    Varsity Tutors
  • examPAL
    Most awarded test prep in the world
    Now free for 30 days

    Available with Beat the GMAT members only code

    MORE DETAILS
    examPAL
  • Kaplan Test Prep
    Free Practice Test & Review
    How would you score if you took the GMAT

    Available with Beat the GMAT members only code

    MORE DETAILS
    Kaplan Test Prep
  • e-gmat Exclusive Offer
    Get 300+ Practice Questions
    25 Video lessons and 6 Webinars for FREE

    Available with Beat the GMAT members only code

    MORE DETAILS
    e-gmat Exclusive Offer
  • PrepScholar GMAT
    5 Day FREE Trial
    Study Smarter, Not Harder

    Available with Beat the GMAT members only code

    MORE DETAILS
    PrepScholar GMAT
  • Economist Test Prep
    Free Trial & Practice Exam
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    Economist Test Prep
  • Veritas Prep
    Free Veritas GMAT Class
    Experience Lesson 1 Live Free

    Available with Beat the GMAT members only code

    MORE DETAILS
    Veritas Prep

How many shares of company X stock

This topic has 5 expert replies and 0 member replies
rsarashi Master | Next Rank: 500 Posts Default Avatar
Joined
24 Dec 2016
Posted:
186 messages
Followed by:
2 members
Upvotes:
5

How many shares of company X stock

Post Sat Sep 02, 2017 10:23 pm
Of the shares of stock owned by certain investor, 30 percent are share of company X stock and 1/7 of the remaining shares are shares of company Y stock. How many shares of company X stock does the investor own?

|) The investors owns 100 shares of company Y stock.

||) The investor owns 200 more shares of company X stock than of company Y stock.

OAD

  • +1 Upvote Post
  • Quote
  • Flag
Post Mon Sep 11, 2017 10:22 am
rsarashi wrote:
Of the shares of stock owned by certain investor, 30 percent are share of company X stock and 1/7 of the remaining shares are shares of company Y stock. How many shares of company X stock does the investor own?

|) The investors owns 100 shares of company Y stock.

||) The investor owns 200 more shares of company X stock than of company Y stock.

OAD
We can let n = the total number of shares, x = the number of company X shares, and y = the number of company Y shares, and we can create the following equations:

0.3n = x

and

(1/7)(0.7)n = y

(1/7)(7/10)n = y

(1/10)n = y

If we can produce a third unique equation with one or more of the variables n, x, or y, or if we know one of the two values of n and y, we can determine the value of x.

Statement One Alone:

The investors owns 100 shares of company Y stock.

Since y = 100, we see that we can determine x. Statement one alone is sufficient to answer the question.

Statement Two Alone:

The investor owns 200 more shares of company X stock than of company Y stock.

We have:

y = 200 + x

Since we have a third unique equation, statement two alone is sufficient to answer the question.

If this is not obvious to you, here is an alternate explanation: In the equation y = 200 + x, we can substitute 0.3n for x and we can substitute 0.10n for y, yielding:

0.10n = 200 + 0.3n

At this point, we see that we can easily solve for n, and then for x.

Answer: D

_________________
Scott Woodbury-Stewart Founder and CEO

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

Post Sun Sep 03, 2017 12:00 pm
Hi rsarashi,

This DS question is essentially just a wordy algebra question. Properly translating the language in the main prompt into "math" will make the rest of the work really easy to do.

We're told that an investor owns some shares of stock, 30% of those total shares are of Stock X and 1/7 or the REMAINING shares are of Stock Y. Before doing anything else, I'm going to translate all of this into algebra:

T = Total shares owned
.3T = number of shares of Stock X

Now, to figure out the number of shares of Stock Y, we need to take the REMAINING shares (in this case, .7T shares) and multiply by 1/7...
.7T(1/7) = (7/10)(T)(1/7) = T/10 = .1T

.1T = number of shares of Stock Y

The question asks for the number of shares of Stock X, so it's asking for the value of .3T (in other words, if you can figure out the value of T, then you can answer the question).

Fact 1: The investor owns 100 shares of Stock Y

This means that .1T = 100.
We CAN solve for T and there is just one answer (and we can save time since we don't have to do the work to see that there's just one answer).
Fact 1 is SUFFICIENT

Fact 2: The investor owns 200 MORE shares of Stock X than Stock Y.

We can translate this into an equation:

.3T = .1T + 200
.2T = 200

Again, we CAN solve for T and there is just one answer.
Fact 2 is SUFFICIENT

Final Answer: D

GMAT assassins aren't born, they're made,
Rich

_________________
Contact Rich at Rich.C@empowergmat.com

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

Post Sun Sep 03, 2017 2:47 am
Quote:
Of the shares of stock owned by a certain investor, 30 percent are shares of Company X stock and 1/7 of the remaining shares are shares of Company Y stock. How many shares of Company X stock does the investor own?

(1) The investor owns 100 shares of Company Y stock.
(2) The investor owns 200 more shares of Company X stock than of Company Y stock.
To determine the ratio of X and Y, plug in a value for the total number of shares.

Since the problem features two fractions -- 30% = 3/10 and 1/7 -- the total number of shares should be a value divisible by both 10 and 7.
Let the total number of shares = 70.
Since 30% of the shares are of Stock X, X = (3/10)(70) = 21.
Remaning shares = 70-21 = 49.
Since 1/7 of the remaining shares are of Stock Y, Y = (1/7)(49) = 7.
Thus:
X:Y = 21:7 = 3:1.

Statement 1: The investor owns 100 shares of Company Y stock
Since X:Y = 3:1 = 300:100, X=300 and Y=100.
SUFFICIENT.

Statement 2: The investor owns 200 more shares of Company X stock than of Company Y stock
Statement 2 implies the same values as Statement 1:
X=300 and Y=100, with the result that X-Y = 300-100 = 200.
SUFFICIENT.

The correct answer is D.

_________________
Mitch Hunt
GMAT Private Tutor
GMATGuruNY@gmail.com
If you find one of my posts helpful, please take a moment to click on the "UPVOTE" icon.
Available for tutoring in NYC and long-distance.
For more information, please email me at GMATGuruNY@gmail.com.

  • +1 Upvote Post
  • Quote
  • Flag
Free GMAT Practice Test How can you improve your test score if you don't know your baseline score? Take a free online practice exam. Get started on achieving your dream score today! Sign up now.
Post Sun Sep 03, 2017 4:27 am
rsarashi wrote:
Of the shares of stock owned by certain investor, 30 percent are share of company X stock and 1/7 of the remaining shares are shares of company Y stock. How many shares of company X stock does the investor own?

|) The investors owns 100 shares of company Y stock.

||) The investor owns 200 more shares of company X stock than of company Y stock.

OAD
Hi rsarashi,

Percentage of stocks of Company X = 30%, thus the percentage of stocks of other companies = 100 - 30% = 70%.

Thus, the percentage of stocks of Company Y = 1/7 of 70% = 10%

=> Number of stocks of Company X = 3*Number of stocks of Company Y

Statement 1: The investors owns 100 shares of company Y stock.

Since we know that the number of stocks of Company X = 3*Number of stocks of Company Y, thus,

Number of stocks of Company X = 3*100 = 300. Sufficient.

Statement 2: The investor owns 200 more shares of company X stock than of company Y stock.

Say the number of stocks of Company Y = y, thus, the number of stocks of Company X = 200 + y

Since we know that the number of stocks of Company X = 3*Number of stocks of Company Y, thus,

200 + y = 3*y

y = 100 => x = 300. Sufficient.

The correct answer: D

Hope this helps!

Download free ebook: Manhattan Review GMAT Quantitative Question Bank Guide

-Jay
_________________
Manhattan Review GMAT Prep

Locations: New York | Jakarta | Nanjing | Berlin | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

Post Sun Sep 03, 2017 6:04 am
rsarashi wrote:
Of the shares of stock owned by certain investor, 30 percent are share of company X stock and 1/7 of the remaining shares are shares of company Y stock. How many shares of company X stock does the investor own?

|) The investors owns 100 shares of company Y stock.

||) The investor owns 200 more shares of company X stock than of company Y stock.

OAD
Target question: What is the value of n?

Given - part a: Of the shares of stock owned by a certain investor, 30 percent are shares of Company X stock ..
If 30% of the shares are Company X, then 70% of the shares are NOT in Company X

Given - part b: ... and 1/7 of the remaining shares are shares of Company Y stock
1/7 of 70% = 10%, so 10% of the shares are in Company Y

Statement 1: The investor owns 100 shares of Company Y stock.
If 30% of the shares are Company X and 10% of the shares are in Company Y, then there are 3 TIMES as many shares in Company X as in Company Y.
(3)(100) = 300, so there are 300 shares in Company X.
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: The investor owns 200 more shares of Company X stock than of Company Y stock.
So, (# of Company X shares) - (# of Company Y shares) = 200
Let T = total number of shares
So, (30% of T) - (10% of T) = 200
Rewrite as 0.3T - 0.1T = 200
Simplify: 0.2T = 200
Solve: T = 1000
So, there are 1000 shares altogether.
30% of the shares are in Company X, and 30% of 1000 = 300
So there are 300 shares in Company X.
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer = D

Cheers,
Brent

_________________
Brent Hanneson – Founder of GMATPrepNow.com
Use our video course along with Beat The GMAT's free 60-Day Study Guide

Check out the online reviews of our course
Come see all of our free resources

  • +1 Upvote Post
  • Quote
  • Flag
GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMAT’s FREE 60-Day Study Guide and reach your target score in 2 months!

Best Conversation Starters

1 lheiannie07 112 topics
2 ardz24 71 topics
3 Roland2rule 69 topics
4 LUANDATO 53 topics
5 swerve 45 topics
See More Top Beat The GMAT Members...

Most Active Experts

1 image description GMATGuruNY

The Princeton Review Teacher

154 posts
2 image description Rich.C@EMPOWERgma...

EMPOWERgmat

107 posts
3 image description Jeff@TargetTestPrep

Target Test Prep

106 posts
4 image description Scott@TargetTestPrep

Target Test Prep

98 posts
5 image description EconomistGMATTutor

The Economist GMAT Tutor

91 posts
See More Top Beat The GMAT Experts