PT is a tangent to a circle with centre O and radius 6 cm. If PT is 8 cm, then length of OP is

• 10 cm

• 12 cm

• 16 cm

• 16 cm

62.

If  then the value of  is

• 
• 

• 3

• 3

In a school, 391 boys and 323 girls have been divided into the largest possible equal classes, so that each class of boys numbers the same as each class of girls. What is the number of classes?

• 23

• 19

• 44

• 44

The average temperature of Monday, Tuesday, Wednesday, Thursday and Friday is 63°. If the ratio of temperature for Monday and Friday is 21 : 25, then what is the temperature of Friday?

• 70°

• 73°

• 75°

• 75°

If  then the value of p³ - q³

• p - q

• pq

• 1

• 1

If x = 93,  y = 93, z = 94, then the value of x² - y² + 10xz + 10yz is

• 104784

• 147840

• 174840

• 174840

D, E, F are the mid-points of the sides BC, CA and AB respectively of a Δ ABC. Then the ratio of the areas of Δ DEF and Δ ABC is:

• 1/2

• 1/4

• 1/8

• 1/16

A circle has its centre at O. A tangent drawn from a point P, which is situated outside the circle, touches the circle at A. If PA= 4 cm and PO = 5 cm, then the length of the radius of the circle is

• 1 cm

• 2 cm

• 3 cm

• 3 cm

If sec (4x - 50°) = cosec (50° - x), then the value of x is

• 45°

• 90°

• 30°

• 30°

An inverted conical shaped vessel is filled with water to its brim. The height of the vessel is 8 cm and radius of the open end is 5 cm. When a few solid spherical metallic balls each of radius  are dropped in the vessel, 25% water is overflowed. The number of balls is:

• 100

• 400

• 200

• 200