If y = 3x, then the value of 10% of y is

This topic has expert replies
Legendary Member
Posts: 2276
Joined: Sat Oct 14, 2017 6:10 am
Followed by:3 members

If y = 3x, then the value of 10% of y is

by VJesus12 » Fri Apr 27, 2018 12:44 am

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

If y = 3x, then the value of 10% of y is

(A) 0.003x
(B) 0.3x
(C) 3x
(D) 30x
(E) 300x

The OA is the option B.

Is not the option A correct? Why not? I need an explanation here. Please.

Legendary Member
Posts: 2898
Joined: Thu Sep 07, 2017 2:49 pm
Thanked: 6 times
Followed by:5 members

by Vincen » Fri Apr 27, 2018 3:35 am
Hi vjesus12.

We have y=3x and we want to calculate the 10% of y, hence $$10\%\cdot y=10\%\cdot3x=\frac{10}{100}\cdot3x=\frac{3}{10}x=0.3x\ .$$ This implies that the correct answer is the option B.

I hope this answer may help you.

User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pm
Location: New York, NY
Thanked: 13060 times
Followed by:1906 members
GMAT Score:790

by GMATGuruNY » Fri Apr 27, 2018 3:56 am
VJesus12 wrote:If y = 3x, then the value of 10% of y is

(A) 0.003x
(B) 0.3x
(C) 3x
(D) 30x
(E) 300x
Let x=10 and y = 3x = 3*10 = 30.
The question stem asks for the value of 10% of y:
10% of y = (10/100)(30) = 3.
Now plug x=10 into the answers to see which yields the target value of 3.
Only B works:
0.3x = 0.3(10) = 3.

The correct answer is B.

Algebra:
Since y = 3x, we get:
10% of y = 0.1y = 0.1(3x) = 0.3x.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 7223
Joined: Sat Apr 25, 2015 10:56 am
Location: Los Angeles, CA
Thanked: 43 times
Followed by:29 members

by Scott@TargetTestPrep » Mon Apr 30, 2018 3:44 pm
VJesus12 wrote:If y = 3x, then the value of 10% of y is

(A) 0.003x
(B) 0.3x
(C) 3x
(D) 30x
(E) 300x
10% of 3x is 0.1 * 3x = 0.3x.

Answer: B

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage