Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2301:30 AM EDT
-02:30 AM EDT
Struggling with GMAT Verbal as a non-native speaker? Harsh improved his score from 595 to 695 in just 45 days—and scored a 99 %ile in Verbal (V88)! Learn how smart strategy, clarity, and guided prep helped him gain 100 points.
Apr 2212:30 AM EDT
-01:30 AM EDT
At one point, she believed GMAT wasn’t for her. After scoring 595, self-doubt crept in and she questioned her potential. But instead of quitting, she made the right strategic changes. The result? A remarkable comeback to 695. Check out how Saakshi did it.
Apr 2308:00 PM PDT
-09:00 PM PDT
Video explanations + diagnosis of 10 weakest areas + 150+ short videos + study plan!
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
08 Dec 2018, 00:19
Kudos
Bookmarks
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
35%
(medium)
Question Stats:
79% (02:43) correct
21%
(02:08)
wrong
based on 71
sessions
History
Date
Time
Result
Not Attempted Yet
If the number of square units in the surface area of a cylinder with a radius of 6 is 1/2 of the number of cubic units in the cylinder, what is the number of square units in the surface area?
A. \(128 \pi\)
B. \(192 \pi\)
C. \(216 \pi\)
D. \(324 \pi\)
E. \(432 \pi\)
A. \(128 \pi\)
B. \(192 \pi\)
C. \(216 \pi\)
D. \(324 \pi\)
E. \(432 \pi\)
eswarchethu135
GMAT 2: 640 Q49 V27
Posts: 276
08 Dec 2018, 05:31
Kudos
Bookmarks
Understanding the question stem is what most important here. No. of cubic units is nothing but the volume of the cylinder. You will get only volume of the cylinder in cubic units and lateral surface area or total surface area in square units.
Surface area of cylinder = \(2\pi r^2 + 2\pi rh\)
Volume of cylinder = \(\pi r^2h\)
\(2\pi r^2 + 2\pi rh\) = \(\frac{1}{2}\pi r^2h\)
r = 6
\(72\pi + 12\pi h = 18\pi h\)
\(6\pi h = 72\pi\)
h = 12
The question is asking to find the surface area of cylinder.
Surface area of cylinder = \(2\pi (6)^2 + 2\pi (6)(12)\)
\(144\pi + 72\pi\)
\(216\pi\)
OPTION: C
Surface area of cylinder = \(2\pi r^2 + 2\pi rh\)
Volume of cylinder = \(\pi r^2h\)
\(2\pi r^2 + 2\pi rh\) = \(\frac{1}{2}\pi r^2h\)
r = 6
\(72\pi + 12\pi h = 18\pi h\)
\(6\pi h = 72\pi\)
h = 12
The question is asking to find the surface area of cylinder.
Surface area of cylinder = \(2\pi (6)^2 + 2\pi (6)(12)\)
\(144\pi + 72\pi\)
\(216\pi\)
OPTION: C
08 Dec 2018, 05:40
Kudos
Bookmarks
The surface area of a cylinder can be found by breaking it down into three parts:
The two circles that make up the ends of the cylinder.
The side of the cylinder, which when unrolled is a rectangle
Area = pr^2+pr^2+ prh+prh where pr^2 is area of circle and prh is area of rectangle when unrolled. (h = height and r =radius)
So, the surface area of a cylinder = p36+p36+6hp+6hp = 72p+12h
the Volume of cylinder is = piR*2*h or base * height
If the number of square units in the surface area of a cylinder with a radius of 6 is 1/2 of the number of cubic units in the cylinder ,
then number of square units in the surface area
= 72p+12h = 1/2 *2*6*h
= 72p+12h = 12h/2
= 72p+12h = 6h
= 12h-6h = -72p
(anyway i will ignore negative sign)
= 6h=72
h= 12
the surface area of a cylinder = 72p+12*12 = 216p
IMO: C
pushpitkc, Gladiator59, chetan2u is my solution correct ? why did i get negative sign in equation above ?
The two circles that make up the ends of the cylinder.
The side of the cylinder, which when unrolled is a rectangle
Area = pr^2+pr^2+ prh+prh where pr^2 is area of circle and prh is area of rectangle when unrolled. (h = height and r =radius)
So, the surface area of a cylinder = p36+p36+6hp+6hp = 72p+12h
the Volume of cylinder is = piR*2*h or base * height
If the number of square units in the surface area of a cylinder with a radius of 6 is 1/2 of the number of cubic units in the cylinder ,
then number of square units in the surface area
= 72p+12h = 1/2 *2*6*h
= 72p+12h = 12h/2
= 72p+12h = 6h
= 12h-6h = -72p
(anyway i will ignore negative sign) = 6h=72
h= 12
the surface area of a cylinder = 72p+12*12 = 216p
IMO: C
pushpitkc, Gladiator59, chetan2u is my solution correct ? why did i get negative sign in equation above ?
