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

 It is currently 16 Nov 2018, 19:19

### 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

## Events & Promotions

###### Events & Promotions in November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
• ### Free GMAT Strategy Webinar

November 17, 2018

November 17, 2018

07:00 AM PST

09:00 AM PST

Nov. 17, 7 AM PST. Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.
• ### GMATbuster's Weekly GMAT Quant Quiz # 9

November 17, 2018

November 17, 2018

09:00 AM PST

11:00 AM PST

Join the Quiz Saturday November 17th, 9 AM PST. The Quiz will last approximately 2 hours. Make sure you are on time or you will be at a disadvantage.

# Garcia purchased two kinds of premium coffee from Harbucks Colorado Co

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 50619

### Show Tags

24 Sep 2017, 23:04
00:00

Difficulty:

85% (hard)

Question Stats:

56% (02:44) correct 44% (02:37) wrong based on 91 sessions

### HideShow timer Statistics

Garcia purchased two kinds of premium coffee from Harbucks Colorado Coffee Emporium. If premium coffee is only sold in one pound bags and each pound of premium mild coffee costs \$2.10 and each pound of premium hearty costs \$2.30, how many pounds of premium mild did Garcia buy?

(1) The total value of the coffee Garcia purchased was \$17.80
(2) If Garcia had purchased 1 more pound of each type of coffee he would have spent \$22.20

_________________
Senior PS Moderator
Joined: 26 Feb 2016
Posts: 3307
Location: India
GPA: 3.12

### Show Tags

25 Sep 2017, 02:00
1
If the quantity of premium mild coffee is x and the quantity of premium hearty is y
From the question stem, the cost of the coffee is 2.1x + 2.3y

1. The total value of the coffee Garcia purchased was \$17.80
2.1x + 2.3y = 17.8
y=5 is the only possibility, where x = 3(Sufficient)

2. If Garcia had purchased 1 more pound of each type of coffee he would have spent \$22.20
2.1(x+1) + 2.3(y+1) = 22.20
2.1x + 2.3y = 17.8(on rewriting the equation) (Sufficient)(Option D)
_________________

You've got what it takes, but it will take everything you've got

Intern
Joined: 25 Jul 2013
Posts: 5

### Show Tags

26 Sep 2017, 00:05
pushpitkc wrote:
If the quantity of premium mild coffee is x and the quantity of premium hearty is y
From the question stem, the cost of the coffee is 2.1x + 2.3y

1. The total value of the coffee Garcia purchased was \$17.80
2.1x + 2.3y = 17.8
y=6 is the only possibility, where x = 0 (Sufficient)

2. If Garcia had purchased 1 more pound of each type of coffee he would have spent \$22.20
2.1(x+1) + 2.3(y+1) = 22.20
2.1x + 2.3y = 17.8(on rewriting the equation) (Sufficient)(Option D)

1) 2.1x + 2.3y = 17.8 .. if y=6 and x=0 >>> 0+ 2.3 x 6 = 13.8 is not equal to 17.8. However, x=3 and y=5 can solely solve the problem>>>> 2.1 x 3 (6.3) + 2.3 x 5 ( 11.5) = 17.8

2) the same thing
Senior PS Moderator
Joined: 26 Feb 2016
Posts: 3307
Location: India
GPA: 3.12

### Show Tags

26 Sep 2017, 08:46
Thanks for bringing that up tjkim88

Sent from my ONEPLUS A3003 using GMAT Club Forum mobile app
_________________

You've got what it takes, but it will take everything you've got

Intern
Joined: 30 Aug 2017
Posts: 15
Location: India
Schools: ISB '19 (A)
GMAT 1: 670 Q47 V35
GPA: 3.9

### Show Tags

08 Oct 2017, 23:39
Can anyone please suggest a simpler way to solve this question? We surely can do trial and error. It will take ages! 178 is not divisible by either 21 or 23. The LCM of 21 and 23 is 483. How do we get 5 and 3?
Intern
Joined: 25 Jul 2013
Posts: 5

### Show Tags

09 Oct 2017, 00:23
1
tejas0999 wrote:
Can anyone please suggest a simpler way to solve this question? We surely can do trial and error. It will take ages! 178 is not divisible by either 21 or 23. The LCM of 21 and 23 is 483. How do we get 5 and 3?

1) total cost is 17.80. focusing on tenth decimal 0.8. 0.1(2.1)a and 0.3(2.3)a should make 0.8. therefore, we can easily to figure out either 0.1X5 + 0.3X1 or 0.3X5 + 0.1X3 (0.1(2.1) X2+0.3(2.3) X2 is too small)
1. 2.1X5 + 2.3X1 = 10.5+2.3= 12.8 (x)
2. 2.1X3 + 2.3X5 = 6.3+11.5= 17.8 (o)
Math Expert
Joined: 02 Aug 2009
Posts: 7035

### Show Tags

09 Oct 2017, 01:38
Bunuel wrote:
Garcia purchased two kinds of premium coffee from Harbucks Colorado Coffee Emporium. If premium coffee is only sold in one pound bags and each pound of premium mild coffee costs \$2.10 and each pound of premium hearty costs \$2.30, how many pounds of premium mild did Garcia buy?

(1) The total value of the coffee Garcia purchased was \$17.80
(2) If Garcia had purchased 1 more pound of each type of coffee he would have spent \$22.20

Yes, it is difficult to test numbers but there are ways to make it less calculation intensive..

Since cost of ONE pound of both is given, so A,B and C are out...

The equation we get is ...
2.1x+2.3y=17.8...........2.1x=17.8-2.3y
As 2.1 is a MULTIPLE of 3, let's make other part multiple of 3....
17.8 is 1+7+8=16 so would leave a Remainder of 1...
But 2.3 will leave a Remainder of 2 when div by 3....
So y will be 3a+2.....
a is 0, y is 2.......17.8-2.3*2=17.8-4.6=13.2, not a multiple of 2.1
a is 1, y is 5....... 17.8-2.3*5=17.8-11.5=6.3=2.1*3..
y as 8 will go beyond 17.8..
So only value y is 5..
Sufficient

D
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

GMAT online Tutor

EMPOWERgmat Instructor
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12871
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170

### Show Tags

10 Dec 2017, 13:42
1
Hi All,

We're told that coffee is only sold in one pound bags, each pound of mild coffee costs \$2.10 and each pound of hearty coffee costs \$2.30. We're asked for the number of pounds of mild coffee that Garcia bought.

1) The total value of the coffee Garcia purchased was \$17.80

Since each type of coffee costs a little more than \$2, this \$17.80 total means that there were likely 8-9 total pounds of coffee purchased. This severely limits the number of possible 'combinations' of coffee, so we can use a bit of 'brute force' math to get to the solution.

Multiples of \$2.10: \$2.10, \$4.20, \$6.30, \$8.40, \$10.50, \$12.60, \$14.70, \$16.80

Multiples of \$2.30: \$2.30, \$4.60, \$6.90, \$9.20, \$11.50, \$13.80, \$16.10

So, how many different ways can you get to \$17.80 using one value from each row (hint: you can 'count down' from \$16.80 and try to find a multiple of \$2.30 that will increase the sum to \$17.80)?

\$6.30 and \$11.50
This is the only option that fits the given information - and the answer to the question is 3 pounds.
Fact 1 is SUFFICIENT

2) If Garcia had purchased 1 more pound of each type of coffee he would have spent \$22.20

Purchasing one more pound of each type would have increased the total by \$2.10+\$2.30 = \$4.40. The total in Fact 2 is \$22.20, which is exactly \$4.40 more than the \$17.80 we were dealing with in Fact 1. Since Fact 1 had just one solution, spending \$4.40 more can only lead to \$22.20 from that one solution.
Fact 2 is SUFFICIENT

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

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

# Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save \$75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****

Re: Garcia purchased two kinds of premium coffee from Harbucks Colorado Co &nbs [#permalink] 10 Dec 2017, 13:42
Display posts from previous: Sort by