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

Redeem

Before adding to her collection, Laura had 207 antique

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 2898
Joined: Thu Sep 07, 2017 2:49 pm
Thanked: 6 times
Followed by:5 members

Before adding to her collection, Laura had 207 antique

by Vincen » Sat Nov 30, 2019 7:32 am
Before adding to her collection, Laura had 207 antique figurines stored in 9 boxes. After adding to her collection, she had 386 figurines in 12 boxes. What was the approximate percent increase in the average number of figurines per box?

A. 9%
B. 33%
C. 40%
D. 50%
E. 86%

[spoiler]OA=C[/spoiler]

Source: Princeton Review
Top
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
Elite Legendary Member
Posts: 10392
Joined: Sun Jun 23, 2013 6:38 pm
Location: Palo Alto, CA
Thanked: 2867 times
Followed by:511 members
GMAT Score:800

by [email protected] » Sat Nov 30, 2019 10:36 am
Hi All,

We're told that before adding to her collection, Laura had 207 antique figurines stored in 9 boxes and that after adding to her collection, she had 386 figurines in 12 boxes. We're asked for the APPROXIMATE PERCENT INCREASE in the average number of figurines per box. This question is based on some standard math formulas (Average & Percent Change) and the word "approximate" means that we can likely round-off some of the values and still get the correct answer.

The "before" average is 207/9 = 23
The "after" average is 386/12 = 32 1/6... which we can round down to 32

Percentage Change = (New - Old)/Old = (Difference)/(Original) = approximately 9/23

9/18 = 50% and 9/27 = 33 1/3%... 9/23 is BETWEEN those values, and there's only one answer that 'fits'....

Final Answer: C

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Top
Legendary Member
Posts: 2499
Joined: Sun Oct 29, 2017 2:04 pm
Followed by:6 members

by swerve » Sat Nov 30, 2019 11:43 am
Vincen wrote:Before adding to her collection, Laura had 207 antique figurines stored in 9 boxes. After adding to her collection, she had 386 figurines in 12 boxes. What was the approximate percent increase in the average number of figurines per box?

A. 9%
B. 33%
C. 40%
D. 50%
E. 86%

[spoiler]OA=C[/spoiler]

Source: Princeton Review
average number of figurines per box before adding to her collection \(= \frac{207}{9} = 23\)
average number of figurines per box before after adding to her collection \(= \frac{386}{12} = 32.1\)

approximate percent increase in the average number of figurines per box \(= \frac{32.1 - 23}{23}\cdot 100\)

\(= 39.85 \approx 40\%\)

Therefore, the correct answer is __C__
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8086
Joined: Sat Apr 25, 2015 10:56 am
Location: Los Angeles, CA
Thanked: 43 times
Followed by:29 members

by Scott@TargetTestPrep » Sun Dec 08, 2019 7:15 pm
Vincen wrote:Before adding to her collection, Laura had 207 antique figurines stored in 9 boxes. After adding to her collection, she had 386 figurines in 12 boxes. What was the approximate percent increase in the average number of figurines per box?

A. 9%
B. 33%
C. 40%
D. 50%
E. 86%

[spoiler]OA=C[/spoiler]

Source: Princeton Review
When Laura had 207 antiques stored in 9 boxes, her average was 207/9 = 23 antiques per box. When she added more, her new average was 386/12 = 32.16, which is about 32 per box. Let's determine the percentage increase, using the formula (New - Old)/Old x 100.

(32 - 23)/23 x 100

9/23 x 100 = 39.1 percent, or about 40%.

Answer: C

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

GMAT/MBA Expert

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

by Brent@GMATPrepNow » Mon Dec 09, 2019 10:21 am
Vincen wrote:Before adding to her collection, Laura had 207 antique figurines stored in 9 boxes. After adding to her collection, she had 386 figurines in 12 boxes. What was the approximate percent increase in the average number of figurines per box?

A. 9%
B. 33%
C. 40%
D. 50%
E. 86%

[spoiler]OA=C[/spoiler]

Source: Princeton Review
Please note that the word approximate typically tells us that we can use some estimation during the solution

INITIAL SITUATION
207/9 = 23 figurines per box

AFTER ADDING TO COLLECTION
386/12 ≈ 32 figurines per box

Percent increase = (100)(new - old)/old
≈ (100)(32 - 23)/23
≈ (100)(9)/23
≈ 900/23
≈ 39

Answer: C

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Post new topic Post Reply
• Page 1 of 1