Last visit was: 18 Dec 2024, 06:42 It is currently 18 Dec 2024, 06:42

Close

GRE Prep 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 GRE 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
User avatar
Retired Moderator
Joined: 07 Jun 2014
Posts: 4815
Own Kudos [?]: 11255 [2]
Given Kudos: 0
GRE 1: Q167 V156
WE:Business Development (Energy and Utilities)
Send PM
avatar
Manager
Manager
Joined: 27 Feb 2017
Posts: 188
Own Kudos [?]: 148 [0]
Given Kudos: 0
Send PM
avatar
Manager
Manager
Joined: 02 May 2018
Posts: 58
Own Kudos [?]: 58 [2]
Given Kudos: 0
Send PM
User avatar
Retired Moderator
Joined: 07 Jun 2014
Posts: 4815
Own Kudos [?]: 11255 [0]
Given Kudos: 0
GRE 1: Q167 V156
WE:Business Development (Energy and Utilities)
Send PM
Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
1
Expert Reply
Explanation

The problem provides the function \(f(x, y) = x^2y\) and also the fact that when a and b are plugged in for x and y, the answer is 6. In other words:

\(f(x, y) = x^2y\)

\(f(a, b) = a^2b = 6\)

The problem asks for the value of f(2a,4b). First, plug 2a in for x and 4b in for y:

\(f(2a, 4b) = (2a)^2(4b)\)

\(f(2a, 4b) = 4a^2(4b)\)

\(f(2a, 4b) = 16a^2b\)

The problem already provides the value for the variables: a2b = 6. Therefore, \(16a^2b = 16(6) = 96\).
Moderator
Moderator
Joined: 02 Jan 2020
Status:GRE Quant Tutor
Posts: 1115
Own Kudos [?]: 974 [0]
Given Kudos: 9
Location: India
Concentration: General Management
Schools: XLRI Jamshedpur, India - Class of 2014
GMAT 1: 700 Q51 V31
GPA: 2.8
WE:Engineering (Computer Software)
Send PM
Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
Given that \(f(x, y) = x^2y\) and \(f(a, b) = 6\) and we need to find the value of \(f(2a, 4b)\)

To find f(a, b) we need to compare what is inside the bracket in f(a, b) and f(x, y)
=> We need to substitute x with a and y with b in \(f(x, y) = x^2y\) to get the value of f(a, b)

=> \(f(a, b) = a^2b\) = 6 given

Similarly, \(f(2a, 4b)\) = \((2a)^2*(4b)\) = \(4a^2 * 4b\) = 16 * \(a^2b\) = 16*6 = 96

So, Answer will be 96
Hope it helps!

Watch the following video to learn the Basics of Functions and Custom Characters

User avatar
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 5090
Own Kudos [?]: 76 [0]
Given Kudos: 0
Send PM
Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
Hello from the GRE Prep Club BumpBot!

Thanks to another GRE Prep 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.
Prep Club for GRE Bot
Re: If f(x, y) = x2y and f(a, b) = 6, what is f(2a, 4b)? [#permalink]
Moderators:
GRE Instructor
88 posts
GRE Forum Moderator
37 posts
Moderator
1115 posts
GRE Instructor
234 posts

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