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

 It is currently 15 Oct 2019, 01:55

### 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

# If during a one-day period the Q train arrives at the station 30% less

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 58344
If during a one-day period the Q train arrives at the station 30% less  [#permalink]

### Show Tags

30 Oct 2018, 03:10
00:00

Difficulty:

25% (medium)

Question Stats:

81% (01:21) correct 19% (01:57) wrong based on 41 sessions

### HideShow timer Statistics

If during a one-day period the Q train arrives at the station 30% less frequently than the B train, and the B train arrives 10% less frequently than the F train, then the Q train`s frequency is what percent of the F train`s frequency?

A. 27
B. 40
C. 60
D. 63
E. 90

_________________
Manager
Joined: 09 Jun 2018
Posts: 188
Location: United States
GPA: 3.95
WE: Manufacturing and Production (Energy and Utilities)
Re: If during a one-day period the Q train arrives at the station 30% less  [#permalink]

### Show Tags

30 Oct 2018, 12:33
Frequency of Q in terms of F = 1*(1-0.3)*(1-0.1) = 1*0.7*0.9 = 0.63 or 63%

Option D
_________________
If you found this relevant and useful, please Smash that Kudos button!
CEO
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2974
Location: India
GMAT: INSIGHT
Schools: Darden '21
WE: Education (Education)
Re: If during a one-day period the Q train arrives at the station 30% less  [#permalink]

### Show Tags

31 Oct 2018, 00:42
Bunuel wrote:
If during a one-day period the Q train arrives at the station 30% less frequently than the B train, and the B train arrives 10% less frequently than the F train, then the Q train`s frequency is what percent of the F train`s frequency?

A. 27
B. 40
C. 60
D. 63
E. 90

Let, Frequency of Q = Q
Let, Frequency of B = B
Let, Frequency of F = F

Q = 0.7 B

and

B = 0.9 F

i.e. Q = 0.7*0.9F = 0.63F

i.e. Frequency of Q is 63% of frequency of train F

_________________
Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

ACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 9701
Location: Pune, India
Re: If during a one-day period the Q train arrives at the station 30% less  [#permalink]

### Show Tags

31 Oct 2018, 02:15
Bunuel wrote:
If during a one-day period the Q train arrives at the station 30% less frequently than the B train, and the B train arrives 10% less frequently than the F train, then the Q train`s frequency is what percent of the F train`s frequency?

A. 27
B. 40
C. 60
D. 63
E. 90

This question just uses the concept of successive percentage changes.

F reduces by 10% and then further reduces by 30% to give Q.

F * (70/100)* (90/100) = Q

F * (63/100) = Q

So Q is 63% of F.

_________________
Karishma
Veritas Prep GMAT Instructor

Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8043
Location: United States (CA)
Re: If during a one-day period the Q train arrives at the station 30% less  [#permalink]

### Show Tags

31 Oct 2018, 18:25
Bunuel wrote:
If during a one-day period the Q train arrives at the station 30% less frequently than the B train, and the B train arrives 10% less frequently than the F train, then the Q train`s frequency is what percent of the F train`s frequency?

A. 27
B. 40
C. 60
D. 63
E. 90

We can create the equations:

Q = 0.7B

And

B = 0.9F

Substitute the second equation into the first, we have:

Q = 0.7(0.9F)

Q = 0.63F

Thus, the Q train’s frequency is 63 percent of the F train’s frequency.

Alternate Solution:

Let’s assume that the F train has 100 arrivals daily. The B train would then have (100)(0.9) = 90 arrivals, and the Q train would have (90)(0.7) = 63 arrivals. Thus, the Q train would have 63/100, or 63%, of the number of arrivals of the F train.

_________________

# Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

Re: If during a one-day period the Q train arrives at the station 30% less   [#permalink] 31 Oct 2018, 18:25
Display posts from previous: Sort by