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 Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 350,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

The only gift certificates that a certain store sold [#permalink]
25 Jun 2012, 01:58

Expert's post

9

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

85% (hard)

Question Stats:

46% (02:49) correct
54% (01:30) wrong based on 322 sessions

The only gift certificates that a certain store sold yesterday were worth either $100 each or $10 each. If the store sold a total of 20 gift certificates yesterday, how many gift certificates worth $10 each did the store sell yesterday?

(1) The gift certificates sold by the store yesterday were worth a total of between $1,650 and $1,800. (2) Yesterday the store sold more than 15 gift certificates worth $100 each.

Diagnostic Test Question: 30 Page: 25 Difficulty: 600

Re: The only gift certificates that a certain store sold [#permalink]
25 Jun 2012, 01:59

3

This post received KUDOS

Expert's post

1

This post was BOOKMARKED

SOLUTION

The only gift certificates that a certain store sold yesterday were worth either $100 each or $10 each. If the store sold a total of 20 gift certificates yesterday, how many gift certificates worth $10 each did the store sell yesterday?

Say the number of $100 certificates sold was \(x\), then the number of $10 certificates sold was \(20-x\).

(1) The gift certificates sold by the store yesterday were worth a total of between $1,650 and $1,800 --> \(1,650<100x+10(20-x)<1,800\) --> \(1,650<90x+200<1,800\) --> \(1,450<90x<1,600\) --> \(145<9x<160\) --> \(16.1<x<17.8\). Since \(x\) is an integer then \(x=17\). Sufficient.

(2) Yesterday the store sold more than 15 gift certificates worth $100 each --> x>15. Clearly insufficient.

Re: The only gift certificates that a certain store sold [#permalink]
25 Jun 2012, 07:57

Hi,

Difficulty level: 650

Let's say, Number of gift certificates worth $100 = x Number of gift certificates worth $10 = y and x+y=20

Using (1), \(1650<100x+10y<1800\) or \(165<10x+y<180\) or \(165<20+9x<180\) (given, x+y=20) or \(145<9x<160\) or \(145/9<x<160/9\) or \(16.1< x < 17.7\) Thus, x = 17. Sufficient.

Re: The only gift certificates that a certain store sold [#permalink]
25 Jun 2012, 17:46

(1) The gift certificates sold by the store yesterday were worth a total of between $1 ,650 and $1,800.

Suff as only one combination of $100 and $10 GC is possible for total ranging from 1650-1800 i.e 17 ($100) and 3 ($10) total 1730, all other combinations within this range do not meet total number of GC condition

(2) Yesterday the store sold more than 15 gift certificates worth $100 each

Insuff as more than 15 can mean 16 and 4, 17 and 3, 18 and 2

Re: The only gift certificates that a certain store sold [#permalink]
25 Jun 2012, 23:30

1

This post received KUDOS

Hi,

Difficulty level: 600

Number of gift certificates worth $100 = x Number of gift certificates worth $10 = y and x+y=20 Statement (1) 1650 < x+y < 1800 This gives us only one possible solution... 1730 Since there has to be 20 gift certificates and x=100$ and y=10$, 1730 is the only number that is between 1650 and 1800 that corresponds with 20 gift certificates Every other solution is out of range e.g. 16 x 100$ + 4 x 10$ = 1640$ or 18 x 100$ + 2 x 10$ = 1820$, both out of the range 1650 < x+y < 1800

Statement (2) clearly insufficient since you can have more than one possible solution. _________________

Re: The only gift certificates that a certain store sold [#permalink]
29 Jun 2012, 03:10

Expert's post

SOLUTION

The only gift certificates that a certain store sold yesterday were worth either $100 each or $10 each. If the store sold a total of 20 gift certificates yesterday, how many gift certificates worth $10 each did the store sell yesterday?

Say the number of $100 certificates sold was \(x\), then the number of $10 certificates sold was \(20-x\).

(1) The gift certificates sold by the store yesterday were worth a total of between $1,650 and $1,800 --> \(1,650<100x+10(20-x)<1,800\) --> \(1,650<90x+200<1,800\) --> \(1,450<90x<1,600\) --> \(145<9x<160\) --> \(16.1<x<17.8\). Since \(x\) is an integer then \(x=17\). Sufficient.

(2) Yesterday the store sold more than 15 gift certificates worth $100 each --> x>15. Clearly insufficient.

Re: The only gift certificates that a certain store sold [#permalink]
28 Dec 2012, 17:50

1

This post received KUDOS

Yes, this question pretty much wants you to understand that A alone is sufficient, otherwise the fallback answer would be C. St II is obviously not sufficient by itself.

Re: The only gift certificates that a certain store sold [#permalink]
06 Jul 2014, 02:46

Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email. _________________

Originally posted on MIT Sloan School of Management : We are busy putting the final touches on our application. We plan to have it go live by July 15...