Is the area of circle X greater than the area of circle Y?

Question

(1) The circumference of circle X is greater than the circumference of circle Z, and the circumference of circle Z is less than the circumference of circle Y.

(2) The radius of circle X is greater than the radius of circle Y.

camlan1990 · Answer

To determine whether the area of circule X is greater than that of circle Y => To determine whether R of X is greater than that of circle Y
(1) The circumference of circle X is greater than the circumference of circle Z, and the circumference of circle Z is less than the circumference of circle Y.
=> R of X > R of Z, R of Z < R of Y 
=> Do not know whether R of X > R of Y 
=> INSUFFICIENT
(2) The radius of circle X is greater than the radius of circle Y
=> SUFFICIENT
=> Ans: B

rohit8865 · Answer

Is the area of circle X greater than the area of circle Y?

(1) The circumference of circle X is greater than the circumference of circle Z, and the circumference of circle Z is less than the circumference of circle Y.

(2) The radius of circle X is greater than the radius of circle Y.

Show Answer

Official Answer

B

Pure algebraic questions like this one are no longer part of the GMAT Data Sufficiency syllabus.

For relevant Data Sufficiency questions, please check the Data Sufficiency forum:
Data Sufficiency Forum

Hemavakade · Answer

Let X = radius of circle x
Let Y = radius of circle y
Let Z = radius of circle z

Statement 1

2* \pi *X > 2* \pi *Z --> X > Z

2* \pi *Z < 2* \pi *Y --> Y > Z

But we don't know if X > Y

ex: X = 4, Y=5, Z = 2 or
X = 5, Y=4, Z = 2

Insufficient

Statement 2

X > Y
we can answer this by squaring both sides and multiplying by  \pi

Sufficient

Answer = B

TheKingInTheNorth · Answer

Is the area of circle X greater than the area of circle Y?

(1) The circumference of circle X is greater than the circumference of circle Z, and the circumference of circle Z is less than the circumference of circle Y.
(2) The radius of circle X is greater than the radius of circle Y.

Kudos for a correct solution.

I have seen a similar question in number format --- whether the underlying concept is similar --- only here they have changed it into geometry .This how Gmat works i guess .

St . 1 is not sufficient .
radius of X = x
radius of Y =y
radius of Z =z

2pie x > 2pie z 
and 
2pie z < 2pie y

There is no relation between x and y . Hence not sufficient .

St 2.
radius of X = x
radius of Y =y
radius of Z =z

x > y

If radius of x is more than y . Then area of x will definitely more than y .

B ans .

Bunuel · Answer

VERITAS PREP OFFICIAL SOLUTION:

Question Type: Yes/No . This question asks whether the area of circle X is greater than the area of circle Y.

Given information from the question stem: This question asks you to determine whether circular region x has a larger area than does circular region y.

Statement 2 seems easier to evaluate so you can start there.

Statement 2 : This statement gives you the relationship between the radius of circle x and that of circle y. Circle x has the larger radius. Since the formula for the area of a circle is πr^2 and π is a constant, it is true that a larger radius definitely means a larger area of the circle. This statement is sufficient. The answer is either B or D.

Statement 1 : This statement compares the circumference of circles x and y with that of circle z. The statement can be rewritten as “circumference x > circumference z” and “circumference y > circumference z.” This does not allow for a comparison of circles x and y; it simply indicates that each is larger than circle z. This information is not sufficient.

The correct answer is B .

Krabhay · Answer

Statement 1. X > Z & Y > Z. 
Since we don’t have any relation between X and Y, we cannot answer this question using statement 1. Hence, Insufficient.
Statement 2. X > Y. Since area of a circle is directly proportional to the radius of the circle, greater radius means greater area. Hence, Sufficient.

bumpbot · Answer

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Is the area of circle X greater than the area of circle Y?

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