It is currently 23 Oct 2017, 12:24

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# There are two right circular cylinders, A and B. The

Author Message
Current Student
Joined: 28 Dec 2004
Posts: 3349

Kudos [?]: 319 [0], given: 2

Location: New York City
Schools: Wharton'11 HBS'12
There are two right circular cylinders, A and B. The [#permalink]

### Show Tags

25 Jul 2008, 08:01
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

There are two right circular cylinders, A and B. The diameter of the base of the cylinder A is twice that of the base of the cylinder B. The height of the cylinder A is half that of the cylinder B. If the radius and the height of the cylinder B are r and h, respectively, what is the absolute value of the difference of the surface areas between the cylinder A and the cylinder B?

A: 4pi r^2
B: 6pi r^2
C: 8pi r^2
D: 10pi r^2
E: 14pi r^2

also what is the ratio of the surface area of A to B?

Kudos [?]: 319 [0], given: 2

Senior Manager
Joined: 14 Mar 2007
Posts: 295

Kudos [?]: 41 [0], given: 3

Location: Hungary

### Show Tags

25 Jul 2008, 08:25
My answer is B. We need to calculate only the surface difference of the circles (top and buttom), because the other parts of the cyliners are equal.

sorry I have no more time to explain further.

Kudos [?]: 41 [0], given: 3

Manager
Joined: 04 Apr 2008
Posts: 215

Kudos [?]: 39 [0], given: 3

Location: Pune

### Show Tags

25 Jul 2008, 08:31
Dimensions of A are 2r and h/2
for B we have r and h
area= 2pi r(r+h)
A= 8pi r*r +2pi r*h
B= 2pi r*r + 2pi r*h
therefore A-B= 6pi r*r
Hence B

Ration wil be A/B i think i dont need to write that
_________________

Every Problem Has a Sloution So keep working
AB

Kudos [?]: 39 [0], given: 3

Current Student
Joined: 31 Aug 2007
Posts: 368

Kudos [?]: 164 [0], given: 1

### Show Tags

25 Jul 2008, 08:58
agree with B...ratio of SA is 4:1

Kudos [?]: 164 [0], given: 1

Re: Surface areas   [#permalink] 25 Jul 2008, 08:58
Display posts from previous: Sort by