BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
GMATLiveTeach 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
Live EA class + 6 months of EA OnDemand
  • Expert-led weekly online sessions
  • EA Masterclass access between classes
View EA class & enroll
Limited cohort · enrollment openTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

130-point score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 559 reviewsTarget Test Prep

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

A ten-gram piece of a certain alloy contains only gold and

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Moderator
Posts: 2575
Joined: Sun Oct 15, 2017 1:50 pmFollowed by: 6 members
by BTGmoderatorLU » Mon Aug 12, 2019 2:30 pm

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty—

Source: Manhattan Prep

A ten-gram piece of a certain alloy contains only gold and silver. If the piece currently contains exactly 3 grams of silver, how many more grams of gold must be added to the piece so that the resulting piece is 10 percent silver?

A. 30
B. 27
C. 25
D. 20
E. 17

The OA is D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pmFollowed by: 1906 members
Location: New York, NY
Thanked: 13060 times
GMAT Score:790

silver

by GMATGuruNY » Mon Aug 12, 2019 2:36 pm
BTGmoderatorLU wrote:Source: Manhattan Prep

A ten-gram piece of a certain alloy contains only gold and silver. If the piece currently contains exactly 3 grams of silver, how many more grams of gold must be added to the piece so that the resulting piece is 10 percent silver?

A. 30
B. 27
C. 25
D. 20
E. 17
Since the resulting piece must be 10 percent silver, the 3 grams of silver in the current piece must constitute 1/10 of the new total weight:
3 = (1/10)t
t = 30 grams
Thus, the weight of the added gold = (weight of the resulting piece) - (weight of the current piece) = 30 - 10 = 20 grams.

The correct answer is D.
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
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8177
Joined: Sat Apr 25, 2015 10:56 amFollowed by: 29 members
Location: Los Angeles, CA
Thanked: 43 times

by Scott@TargetTestPrep » Sat Aug 24, 2019 4:18 am
BTGmoderatorLU wrote:Source: Manhattan Prep

A ten-gram piece of a certain alloy contains only gold and silver. If the piece currently contains exactly 3 grams of silver, how many more grams of gold must be added to the piece so that the resulting piece is 10 percent silver?

A. 30
B. 27
C. 25
D. 20
E. 17

The OA is D
Let x = the number of grams of gold that must be added to the piece so that the resulting piece is 10 percent silver. We can create the equation:

3/(10 + x) = 1/10

10 + x = 30

x = 20

Alternate Solution:

As the number of grams of silver in the alloy after the addition of gold does not change, the resulting alloy will contain 3 grams of silver as well. If the resulting piece is 10% silver, then the resulting piece must weigh 30 grams (so that 10% of it is 3 grams). Since the original piece was 10 grams, 30 - 10 = 20 grams of gold must be added.

Answer: D

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
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770

by Brent@GMATPrepNow » Sat Aug 24, 2019 6:14 am
BTGmoderatorLU wrote:Source: Manhattan Prep

A ten-gram piece of a certain alloy contains only gold and silver. If the piece currently contains exactly 3 grams of silver, how many more grams of gold must be added to the piece so that the resulting piece is 10 percent silver?

A. 30
B. 27
C. 25
D. 20
E. 17

The OA is D
GIVEN: The piece weighs 10 grams. The piece contains 3 grams of silver, which means the remaining 7 grams are gold
Let x = the number of EXTRA grams of gold needed for the piece to be 10 percent silver.
With the addition of x grams of gold, the NEW weight of the piece = 10 + x

How many more grams of gold must be added to the piece so that the resulting piece is 10 percent silver?
We want: (grams of silver)/(TOTAL weight of piece) = 10%
Fill in values to get: 3/(10 + x) = 1/10 (aka 10%)
Cross multiply to get: (1)(10 + x) = (3)(10)
Simplify to get: 10 + x = 30
Solve: x = 20

Answer: D

Cheers,
Brent


10 + x = 30

x = 20
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1