The ratio of the radius to the height of a right cone is 3:4. Then the

Question

The ratio of the radius to the height of a right cone is 3:4. Then the ratio of total surface area to curved surface of the cone is____.

Options:

A . 2:3

B . 3:5

C . 7:9

D . 8:5

Answer: Option D
:
D
Given that,
r:h = 3:4
Letr =

3 x

and h =

4 x

From the relation

l^{2} = h^{2} + r^{2}

,
The Slant height:

l = \sqrt{(3 x)^{2} + (4 x)^{2}}

\Rightarrow l = 5 x

We know that,
Total surface area of cone

= π r (r + l)

Curved surface area of cone

= π r l

Hence, the required ratio

= \frac{T o t a l s u r f a c e a r e a o f c o n e}{C u r v e d s u r f a c e a r e a}

= \frac{π r (r + l)}{π r l}

= \frac{π \times 3 x (3 x + 5 x)}{π \times 3 x \times 5 x}

= 8 : 5

Was this answer helpful ?

Next Question

More Questions on This Topic :

Question 1. The water in a cubical tank of side 10m is transferred to completely fill a cuboidal tank of length 5m and breadth 10 a....Then the height of the cuboidal tank (in metres) is ___

Question 2. Meena needs to serve mango juice to her guests in cylindrical tumblers of radius 7 cm up to a height of 10 cm. If s....wants to serve 25 guests, how much juice should she prepare?

Question 3. The cost of painting the curved surface area of a cylindrical pillar of height 10 m and radius 3.5 m at ₹ 10....radius 3.5 m at ₹ 10/- per sq. meter is ₹ 2200/-. (use π=227)

Question 4. A juice seller fills juice into cylindrical glasses from a big cylindrical container of height 35.2 cm and radius 1....4 cm. The amount he earns by selling the juice is ____. (Use π=227)

Question 5. A water container can hold 40 litres of water. Then the total number of ice cubes of side 5 cm which the container....side 5 cm which the container can hold is ____.

Question 6. A 3×3 Rubik's cube has a total surface area of 54 cm2. The area occupied by every single red tile of....by every single red tile of the cube is ___________ .

Question 7. Pavan drew a △ABC right angled at B. He says if the right angle triangle is rotated along AB then it will result in _....triangle is rotated along AB then it will result in ___

Question 8. A big iron boiler tank which is cylindrical in shape is open at the top. Its height is 10 m and radius is 7 m. It g....days it will take to corrode completely is ____ . (use π=227)

Question 9. The volume of a cone of radius 7 cm and slant height 14 cm is ______.(use π=227)....

Question 10. A hemispherical bowl fits exactly on the flat surface of a right circular cone whose height is 5 cm and radius is 3.5 c....is 3.5 cm. The volume of the solid formed is______.

Chapter 1 - GLOBAL STEEL SCENARIO & INDIAN STEEL INDUSTRY Part 1 : (13-04-2024) INDUSTRY AND COMPANY AWARENESS (ICA)

Direction Sense Test Part 1 Reasoning (Hindi)

Chapter 1 - RMHP / OHP / OB & BP Part 1 : (14-02-2024) GPOE

Cube & Cuboid Part 1 Reasoning (Hindi)

Data Interpretation (DI) Basic Concept Reasoning (Hindi)

Counting Figures Part 1 Counting Of Straight Lines Reasoning (Hindi)

Sail E0 free webinar Webinars

Real Numbers Part 7 Class 10 Maths

Real Numbers Part 1 Class 10 Maths

Polynomials Part 1 Class 10 Maths

Pie Chart - Test Paper 1 Data Interpretation Reasoning & DI

Tabulation - Test Paper 2 Data Interpretation Reasoning & DI

Test Paper 1 Direction Sense Test Reasoning & DI

ICA , RDIC,GFM Free Modal Test Paper - Non - Technical Branch Old Syllabus 2022 - SAIL Junior Officer E0

GFM Combined 1 Free Revision Test SAIL JO E-0