It is currently 21 Oct 2017, 00:21

Close

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
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.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

For the first 3 months of last year, the average daily rainfall in Lan

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41891

Kudos [?]: 129061 [0], given: 12190

For the first 3 months of last year, the average daily rainfall in Lan [#permalink]

Show Tags

New post 15 Aug 2017, 01:09
Expert's post
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

88% (00:48) correct 12% (00:40) wrong based on 59 sessions

HideShow timer Statistics

For the first 3 months of last year, the average daily rainfall in Lancaster was 6cm. For last year as a whole, the average daily rainfall was 12cm. What was the average daily rainfall for the last 9 months of last year?

A. 14cm
B. 16cm
C. 18cm
D. 24cm
E. 30cm
[Reveal] Spoiler: OA

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 129061 [0], given: 12190

BSchool Forum Moderator
User avatar
P
Joined: 26 Feb 2016
Posts: 1465

Kudos [?]: 596 [0], given: 16

Location: India
Concentration: General Management, Leadership
WE: Sales (Retail)
Premium Member CAT Tests
Re: For the first 3 months of last year, the average daily rainfall in Lan [#permalink]

Show Tags

New post 15 Aug 2017, 01:54
It has been given that the average daily rainfall in Lancaster for the first 3 months was 6 cm.
Similarly, the average for the entire year is given to be 12 cm.

Let x be the average daily rainfall for each of the last 9 months.

Forming an equation, \(\frac{3*6 + 9*x}{12} = 12\)
Cross multiplying,
\(18 + 9x = 144\)
\(9x = 126\)
\(x = 14\)

Therefore, the average daily rainfall for the last 9 months of last year is \(14(Option A)\)
_________________

Stay hungry, Stay foolish

2017-2018 MBA Deadlines

Class of 2020: Rotman Thread | Schulich Thread
Class of 2019: Sauder Thread

Kudos [?]: 596 [0], given: 16

Director
Director
avatar
P
Joined: 22 May 2016
Posts: 819

Kudos [?]: 266 [0], given: 552

For the first 3 months of last year, the average daily rainfall in Lan [#permalink]

Show Tags

New post 15 Aug 2017, 16:21
Bunuel wrote:
For the first 3 months of last year, the average daily rainfall in Lancaster was 6cm. For last year as a whole, the average daily rainfall was 12cm. What was the average daily rainfall for the last 9 months of last year?

A. 14cm
B. 16cm
C. 18cm
D. 24cm
E. 30cm


|__A__|__n__|__S___|
|__6__|__3__|__18__|
|_12__|_12__|__144_|
|_14__|__9__|__126_|

12 months' sum - 3 months' sum = 9 months' sum for daily average rainfall

144 - 18 = 126 cm total (sum) for 9 months

S/n = A

126 cm/9 months = 14 cm per month average daily rainfall

Answer A

Kudos [?]: 266 [0], given: 552

Expert Post
Target Test Prep Representative
User avatar
S
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 1545

Kudos [?]: 837 [0], given: 5

Re: For the first 3 months of last year, the average daily rainfall in Lan [#permalink]

Show Tags

New post 18 Aug 2017, 09:14
Bunuel wrote:
For the first 3 months of last year, the average daily rainfall in Lancaster was 6cm. For last year as a whole, the average daily rainfall was 12cm. What was the average daily rainfall for the last 9 months of last year?

A. 14cm
B. 16cm
C. 18cm
D. 24cm
E. 30cm


Let’s assume that each month has exactly 30 days. For the first 3 months, there were 6 x 30 x 3 inches of rainfall, and for the entire year, there were 12 x 30 x 12 inches of rainfall.

Finally, for the last 9 months, the average daily rainfall was:

(12 x 30 x 12 - 6 x 30 x 3)/(30 x 9) = (12 x 12 - 6 x 3)/9 = 126/9 = 14 cm

Answer: A
_________________

Jeffery Miller
Head of GMAT Instruction

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Kudos [?]: 837 [0], given: 5

Senior Manager
Senior Manager
User avatar
G
Joined: 27 May 2012
Posts: 400

Kudos [?]: 85 [0], given: 478

Premium Member
For the first 3 months of last year, the average daily rainfall in Lan [#permalink]

Show Tags

New post 18 Oct 2017, 04:41
JeffTargetTestPrep wrote:
Bunuel wrote:
For the first 3 months of last year, the average daily rainfall in Lancaster was 6cm. For last year as a whole, the average daily rainfall was 12cm. What was the average daily rainfall for the last 9 months of last year?

A. 14cm
B. 16cm
C. 18cm
D. 24cm
E. 30cm


Let’s assume that each month has exactly 30 days. For the first 3 months, there were 6 x 30 x 3 inches of rainfall, and for the entire year, there were 12 x 30 x 12 inches of rainfall.

Finally, for the last 9 months, the average daily rainfall was:

(12 x 30 x 12 - 6 x 30 x 3)/(30 x 9) = (12 x 12 - 6 x 3)/9 = 126/9 = 14 cm

Answer: A


Hi JeffTargetTestPrep,

I was confused in this question too! It doesn't say MONTHY average rather it says DAILY average. Hence we need to know the number of days in each month to find the total rainfall, just as you have done .
But how can we assume that each month has 30 days .

If the question was " The monthly average for the first 3 months was 6 cm" then it would be ok to do 6 *3 to get the total rainfall of the first 3 months. Would it not ?
Please let me know what do you feel.
Thanks.
_________________

- Stne

Kudos [?]: 85 [0], given: 478

For the first 3 months of last year, the average daily rainfall in Lan   [#permalink] 18 Oct 2017, 04:41
Display posts from previous: Sort by

For the first 3 months of last year, the average daily rainfall in Lan

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.