GMAT 650+ Math Question 20 | Number Properties

Face Values & Place Value | Data Sufficiency Practice

The given question is GMAT 650 level data sufficiency question testing concepts in number properties and number systems. A very interesting GMAT practice question to understand place value and face value of numbers.

Question 20: x is a two-digit positive integer. y is obtained by multiplying the tens place of x by 2. Is y > \\frac{x}{6})?

Statement 1: 20 < x < 30
Statement 2: y = 10

Get to Q51 in GMAT Quant

Online GMAT Course
@ INR 3500

Video Explanation

GMAT Live Online Classes

Start Tue, Oct 12, 2021

Explanatory Answer | GMAT Number Properties DS

Step 1: Decode the Question Stem

Is y > \\frac{x}{6})?
We can rewrite the question as "Is 6y > 6?"

Step 2: Evaluate Statement 1 ALONE

Statement 1: 20 < x < 30
x takes values from 21 to 29.
For all these values of x, y = 2 × 2 = 4. So, 6y = 24

Approach: Counter Example
Example: x = 21, 6y is greater than x. Answer: Yes
Counter example: x = 25, 6y is not greater than x. Answer: No
Answer to the question "Is 6y > x?" is sometimes YES and sometimes NO.

We are not able to find a conclusive answer to the question using statement 1 ALONE.
Statement 1 alone is NOT Sufficient.
Eliminate answer options A and D.

Step 3: Evaluate Statement 2 ALONE

Statement 2: y = 10
So, the tens place of x is 5.
Values that x can take are 50 ≤ x ≤ 59
Because y = 10, 6y = 60
For all values of x in the range 50 ≤ x ≤ 59, 6y > x
The answer to the question "Is 6y > x?" is a conclusive YES.

We are able to answer the question a definite YES using statement 2 ALONE.
Statement 2 AlONE is Sufficient.
Eliminate answer options C and E.

Choice B is the correct answer.

GMAT Online Course
Try it free!

Register in 2 easy steps and
Start learning in 5 minutes!

★ Sign up

Already have an Account?

★ Login

GMAT Live Online Classes

Next Batch Oct 12, 2021

★ GMAT Live Info

GMAT Coaching in Chennai

Next Batch
after Lockdown

★ GMAT Class Info

GMAT Coaching in Chennai

Sign up for a Free Demo of our GMAT Classes in Chennai

★ Schedule Demo

GMAT Hard Math Videos On YouTube

GMAT Sample Questions | Topicwise GMAT Questions

Where is Wizako located?

Wizako - GMAT, GRE, SAT Prep
An Ascent Education Initiative
14B/1 Dr Thirumurthy Nagar 1st Street
Chennai 600 034. India

How to reach Wizako?

Phone: (91) 44 4500 8484
Mobile: (91) 95000 48484
WhatsApp: WhatsApp Now
Leave A Message