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The volume of a right circular cylinder is 392π cm^{3} and its height is 8 cm. Find the radius? 
A) 6 cm B) 7 cm C) 8 cm D) 9 cm Correct Answer : 7 cm Explanation : Volume of a cylinder = πr^{2}h 
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If the height of right circular cylinder is 10 cm and radius of its base is 4 cm, find its total surface area? 
A) 350 cm² B) 351 cm² C) 352 cm² D) 353 cm² Correct Answer : 352 cm² Explanation : Total Surface Area of a cylinder= 2πrh + 2πr^{2} = 2πr(h + r) 
Length,Width and Height of a cuboid are in the ratio of 6:3:5. If the total surface area of cuboid is 1134 cm2 then find its Length, Width and Height. 
A) 18, 9, 15
B) 17, 10, 15
C) 12, 15, 9
D) 11, 13, 16
Correct Answer : 18, 9, 15 Explanation : Let the length,width and height of the cuboid are 6x,3x,5x respectively. The total surface area of cuboid ,2*(lb + bh + lh) = 1134 Hence the dimensions of cuboid will be 18, 9, 15. 
If the surface area of two spheres are in the ratio 9:16, then the ratio of their volumes will be? 
A) 9:16 B) 16:9 C) 27:64 D) 3:4 Correct Answer : 27:64 Explanation : Let the radius of two sphere be r and R As is given, 4πr^{2}/4πR^{2 }= 9/16 ratio of their volume = (4πr^{3}/3) / (4πR^{3}/3) 
The volume of a cube is 512 cm^{3}, Its surface area is ? 
A) 64 cm^{2} B) 256 cm^{2} C) 384 cm^{2} D) 512 cm^{2} Correct Answer : 384 cm^{2} Explanation : Volume =a^{3} = 512 cm^{3}= 8 x 8 x 8 
A box is of 10 cm long, 8 cm broad and 5 cm high. What is the longest possible length of a pencil that can be put in ? 
A) √150 cm B) √98 cm C) 3√21 cm D) 3√52 cm Correct Answer : 3√21 cm Explanation : Since, the box is in the form of a cuboid. longest possible length of a pencil=>diagonal of cuboid=√(l^{2} +b^{2} +h^{2}) 
Find the height of the cylinder whose volume is 551 m^{3} and the area of the base is 36.5 m^{2} ? 
A) 7 m B) 10.5 m C) 14 m D) 15 m Correct Answer : 14 m Explanation : Base of cylinder => Area of circle = πr^{2 }= 36.5 m^{2} ^{ }Volume of cylinder = πr^{2}h = Area base * height = 36.5 * h 

If the volume and surface are of a sphere are numerically the same then its radius is ? 
A) 1 unit B) 2 unit C) 3 unit D) 4 unit Correct Answer : 3 unit Explanation : Volume = (4/3)πr^{3} as per question,^{ }4/3 πr^{3} = 4πr^{2} 
A cylinder and a cone have the same height and same radius of the base. The ratio between the volumes of the cylinder and the cone is ? 
A) 1 : 3
B) 3 : 1
C) 1 : 2
D) 2 : 1
Correct Answer : 3 : 1 Explanation : Volume of Cylinder = πr^{2}h Volume of cone = (1/3)πr^{2}h Ratio of their volumes = [πr^{2}h] / [(1/3)πr^{2}h] => 3/1 => 3 : 1 
A sphere of radius r has the same volume as that of a cone with circular base of radius r. Find the height of the cone ? 
A) 2r B) r/3 C) 4r D) (2/3)r Correct Answer : 4r Explanation : Volume of sphere = Volume of cone 

If the volume of the cube is 1331 m^{3}, then the total surface area of the cube is(in m^{2}): 
A) 648
B) 484
C) 726
D) 216
Correct Answer : 726 Explanation : Let the side of Cube is a Then, 
The areas of two circles are in the ratio 1:2. Find the ratio of their radius? 
A) 1:2
B) 1:3
C) 1:√2
D) 1:4
Correct Answer : 1:√2 Explanation : Ratio of the areas of the circles = π(r_{1})^{2} : π(r_{2})^{2 } =1:2

A hall is 12m long and 8m broad. If the sum of the area of the floor and the ceiling is equal to the sum of the area of the four walls. Find the height of the hall (in m) 
A) 4.8
B) 6.4
C) 8.3
D) 3.2
Correct Answer : 4.8 Explanation : Area of 4 walls of a room = (l*h)+(b*h)+(l*h)+(b*h) =2(l*h)+2(b*h) = 2h(l+b) We have, 
If each side of a cube is 3 centimeter,then its surface area is : 
A) 54 Cubic Centimeter B) 9 Square Centimeter C) 54 Square Centimeter D) None of these Correct Answer : 54 Square Centimeter Explanation : if side of the square as “a”, then 
A 5 cm cube is cut into as many 1 cm cubes as possible. What is the ratio of the surface area of the larger cube to the smaller cubes? 
A) 1/6 B) 1/5 C) 1/25 D) 1/125 Correct Answer : 1/5 Explanation : The volume of the original cube = 5^{3} = 125 cm^{3}. 
If the surface area of sphere is 346.5 cm2, then its radius is [ taking π=22/7 ]? 
A) 5.25 cm B) 7.25 cm C) 3.25 cm D) 9.25 cm Correct Answer : 5.25 cm Explanation : Surface area of sphere= 4πr^{2} 
If cost of painting is Rs 12 per sq meter of surface area, how much will it cost to paint all surfaces of a solid right circular cylinder with height of 9 meters and base area of 154 sq meters? 
A) Rs. 8448 B) Rs. 9372 C) Rs. 1540 D) Rs. 3180 Correct Answer : Rs. 8448 Explanation : Base area of cylinder = πr^{2} = 154 Then, Total Surface Area of cylinder = 2πr(h + r) = 2π*7*(9 + 7) Hence, Cost of painting = 12 * 704 