A copper wire is bent in the shape of a square of area 81 cm². If the same wire is bent in the form of a semicircle, the radius (in cm) of the semicircle is 

• 16

• 14

• 10

• 7

The perimeter of a triangle is 40 cm and its area is 60 cm². If the largest side measures 17 cm, then the length (in cm) of the smallest side of the triangle is

• 4

• 6

• 8

• 15

93.

A bicycle wheel makes 5000 revolutions in moving 11 km. The diameter of the wheel (in cm) is

• 35

• 55

• 65

• 70

If a wire is bent into the shape of a square, then the area of the square so formed 81 cm². When the wire is rebent into semicircular shape, then the area (in cm²) of the semi-circle will be 

• 22

• 44

• 77

• 154

At each corner of the triangular filed of sides 26 m, 28 m and 30 m, a cow is tethered by a rope of length 7m. The area (in m²) ungrazed by the cows is

• 336

• 259

• 154

• 77

If the radius of a circle is increased by 50%, its area is increased by

• 125%

• 100%

• 75%

• 50%

A rectangular garden is 100 m x 80 m. There is a path along the garden and just outside it. Width of the path is 10 m. The area of the path is

• 1900 sq m

• 2400 sq m

• 3660 sq m

• 4000 sq m

A rail road curve is to be laid out on a circle. What radius should be used if the track is to change direction by 25° in a distance of 40 m?

• 91.64 m

• 90.46 m

• 89.64 m

• 93.64 m

When a pendulum of length 50 cm oscillates, it produces an arc of 16 cm. The angle so formed in degree measure is (approx.)

• 18°25'

• 18°35'

• 18°20'

• 18°08'

Side AB of rectangle ABCD is divided into four equal parts by points x, y, z. The ratio of the

is

• 1/6

• 1/9

• 1/8

• 1/7