Mental Ability Test Surface area and Volume T1

When the radius of a circle is decreased by 50%, the area of the circle

• (A) decreases by 50%

• (B) decreases by 75%

• (C) increases by 100% 

• (D) decreases by 100%

Consider Circle inscribed in Square with side 14 cm, what is the ratio of the areas of square and circle?

• (A) 4:π

• (B) 2:π

• (C) 1:π

• (D) 8:π

A fish tank is in the form of a cuboid whose external measures are 80 cm × 40 cm × 30 cm. The base, side faces and back face are to be covered with a colored paper. Find the area of the paper needed.

• (A) 9000 cm²

• (B) 3000 cm²

• (C) 5000 cm²

• (D) 8000 cm²

The length, width and height ratio of a cuboidal room is

7 : 5 : 4 and its entire surface area is 2656 sq. cm.

Find its width.

• (A) 16 cm

• (B) 20 cm

• (C) 28 cm

• (D) 32 cm

A cuboid is of dimensions 60 cm × 54 cm × 30 cm. How many small cubes with side 6 cm can be placed in the given cuboid?

• (A) 450

• (B) 300

• (C) 520

• (D) 424

Find the number of bricks, each measuring 24 cm × 12 cm × 8 cm, required to construct a wall 24 m long, 8m high and 60 cm thick if 10% of the wall is filled with mortar?

• A) 450   

• B) 4500   

• C) 45000     

• D) 450000

There are 3 stair-steps. Each stair-step has width 25 cm, height 12 cm and length 50 cm. How many bricks have been used in it if each brick is 12.5 cm x 6.25 cm x 4 cm.

• (A) 320

• (B) 242

• (C) 288 

• (D) 186

Water is pouring into a cuboidal reservoir at the rate of 60 liters per minute. If the volume of reservoir is 108 m³, find the number of hours it will take to fill the reservoir.

• (A) 20 Hours

• (B) 30 Hours

• (C) 24 Hours

• (D) 36 Hours

A cuboidal Ice of sides 9 cm, 27 cm and 24 cm is melted to form a cube. What is the ratio between the total surface area of the cuboid and that of the cube.

• (A) 41 : 35

• (B) 41 : 36

• (C) 47 : 38

• (D) 49 : 36

The length and breadth ratio of an auditorium is 3:2. If the roof area is 216 Sq. Meters and the area of the four walls is 480 sq. meters, then what will be the height of the auditorium.

• (A) 6 m 

• (B) 10 m

• (C) 8 m

•   (D) 12 m