Question : The volume of a cylinder is 4312 cm3. Its curved surface area is one-third of its total surface area. Its curved surface area (in cm2) is:
(Take $\pi=\frac{22}{7}$ )
Option 1: 572 cm2
Option 2: 528 cm2
Option 3: 660 cm2
Option 4: 616 cm2
Correct Answer: 616 cm 2
Solution :
According to the question,
Curved surface area = $\frac{\text{Total surface area}}{3}$
⇒ $2\pi rh = \frac{2\pi r(h + r)}{3}$
⇒ $3h = (h + r)$
⇒ $2h = r$
Now,
The volume of a cylinder = 4312 cm
3
⇒ $\pi r^2h = 4312$
⇒ $\frac{22}{7}\times r^2\times \frac{r}{2} = 4312$
⇒ $r^3 = 14^3$
⇒ $r = 14$
So, $h = \frac{r}{2} = \frac{14}{2} = 7$
Now, Curved Surface Area = $2\pi rh$
= $2 \times \frac{22}{7} \times 14 \times 7$
= $616$ cm
2
Hence, the correct answer is 616 cm
2
.
Related Questions
Know More about
Staff Selection Commission Combined Grad ...
Result | Eligibility | Application | Selection Process | Preparation Tips | Admit Card | Answer Key
Get Updates Brochure
Your Staff Selection Commission Combined Graduate Level Exam brochure has been successfully mailed to your registered email id “”.
Upcoming Exams
Trending Articles around SSC CGL
