### Bookshelf

 Total GMAT Math Jeff's complete Quant guide, on sale now!
 Total GMAT Verbal Everything you need to ace GMAT Verbal!
 New: GMAT 111 Improve every aspect of your GMAT prep!

Guides To the Official Guide
(Updated for new editions!)

1,800 Practice Quant Questions

GMAT Question of the Day

GMAT Official Guide
OG Math | OG Verbal

Beginner's Guide to the GMAT

GMAT Hacks Affiliate Program

### Resources

MBA.com
GMAC Official Site
Free GMATPrep Practice Tests

Stacy Blackman Consulting
Book | Essay Guides

GRE HQ
Total GRE Math

Ultimate SAT Verbal

## Official Guide Explanation:Data Sufficiency #60

Background

This is just one of hundreds of free explanations I've created to the quantitative questions in The Official Guide for GMAT Quantitative Review (2nd ed.). Click the links on the question number, difficulty level, and categories to find explanations for other problems.

These are the same explanations that are featured in my "Guides to the Official Guide" PDF booklets. However, because of the limitations of HTML and cross-browser compatibility, some mathematical concepts, such as fractions and roots, do not display as clearly online.

Question: 60
Page: 157
Difficulty: 5 (Moderate)
Category 1: Algebra > Linear Equations-Two Unk >
Category 2: Geometry > Quadrilaterals >
Category 3: Word Problems > Geometry Problems >

Explanation: Perimeter is given by 2l + 2w, so for this garden, 2l + 2w = 360. To solve for the length, we need another linear equation. Statement (1) is sufficient: l = 2w can be combined with the perimeter equation to solve for each variable. Statement (2) is insufficient: if the length is greater than the width, l - w = 60; if not, w - l = 60. Since we don't know which equation is true, we can't find the length of the garden. Choice (A) is correct.

[Note: The answer given in the book is (D). The explanation in the book suggests that the length must be longer than the width, which is not true. It's also not consistent with other published GMAT questions. Until and unless the wording of the question is changed in future editions, (A) is the correct answer.]

 You should follow me on Twitter. While you're at it, take a moment to subscribe to GMAT Hacks via RSS or Email.

 Total GMAT Math The comprehensive guide to the GMAT Quant section. It's "far and away the best study material available," including over 300 realistic practice questions and more than 500 exercises! Click to read more.