GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 15 Dec 2019, 11:33

### 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

# There are two right circular cylinders A and B. The height and the dia

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 59730
There are two right circular cylinders A and B. The height and the dia  [#permalink]

### Show Tags

16 Oct 2018, 04:45
00:00

Difficulty:

25% (medium)

Question Stats:

76% (01:36) correct 24% (01:29) wrong based on 61 sessions

### HideShow timer Statistics

There are two right circular cylinders A and B. The height and the diameter of cylinder B are each twice those of cylinder A. If the capacity of cylinder A is 10 barrels, what is the capacity of cylinder B, in barrels?

(A) 36
(B) 40
(C) 60
(D) 80
(E) 100

_________________
Manager
Joined: 14 Jun 2018
Posts: 211
Re: There are two right circular cylinders A and B. The height and the dia  [#permalink]

### Show Tags

16 Oct 2018, 06:22
Volume of larger barrel = $$π (2r)^2 * 2h = 8πr^2$$

Capacity of $$πr^2h$$ = 10 barrels
Capacity of $$8πr^2$$ = 80 barrels
Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8701
Location: United States (CA)
Re: There are two right circular cylinders A and B. The height and the dia  [#permalink]

### Show Tags

17 Oct 2018, 19:07
Bunuel wrote:
There are two right circular cylinders A and B. The height and the diameter of cylinder B are each twice those of cylinder A. If the capacity of cylinder A is 10 barrels, what is the capacity of cylinder B, in barrels?

(A) $36 (B)$40
(C) $60 (D)$80
(E) \$100

We can let h and r be the height and radius of cylinder A. Thus we have πr^2 * h = 10. Since the height and the diameter of cylinder B are each twice those of cylinder A, we have the height and radius of cylinder B as 2h and 2r, respectively (notice that if the diameter of cylinder B is twice that of cylinder A, its radius is also twice that of cylinder A). So the capacity (or volume) of cylinder B is:

V = π(2r)^2 * (2h) = π(4r^2) * (2h) = 8πr^2 * h

Since πr^2 * h = 10, the capacity of cylinder B is 8(10) = 80.

_________________

# Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

Re: There are two right circular cylinders A and B. The height and the dia   [#permalink] 17 Oct 2018, 19:07
Display posts from previous: Sort by