CBSE [All India]_X_Mathematics_2011_Set I

 The roots of the equation
x² – 3x –m(m+3)=0, where m is a constant, are 

(A)          m,  m+3 
(B)    –m,  m+3
(C)            m, - (m+3)
(D)    –m, - (m+3)

If the common difference of an A.P. is 3, then a₂₀ – a₁₅ is
(A) 5
(B) 3
(C) 15
(D) 20

In Figure, O is the centre of a circle, PQ is a chord and PT is the tangent at P. If                                                                                POQ=70°, then TPQ is equal to    
   
(A) 55°
(B) 70°
(C) 45°
(D) 35°

In figure, AB and AC are tangents to the circle with centre O such that BAC =40°. Then BOC is equal to
                         
(A) 40°
(B) 50°
(C) 140°
(D) 150°

 The perimeter (in cm) of a square circumscribing a circle of radius a cm is 

(A) 8a
(B) 4a
(C) 2a
(D) 16a

The radius (in cm) of the largest right circular cone that can be cut out from a cube of edge 4.2 cm is

(A) 4.2 
(B) 2.1
(C) 8.4
(D) 1.05

A tower stands vertically on the ground. From a point on the ground which is 25 m away from the foot of the tower, the angle of elevation of the top of the tower is found to be 45°. Then the height (in meters) of the tower is 

(A)    252

(B)    253

(C)    25

(D)   12.5

If P(a/2, 4) is the mid-point of the line - segment joining the points A(-6, 5) and B(- 2, 3), then the value of a is 

(A) – 8

(B)           3

(C) – 4

(D)          4

If A and B are the points (- 6, 7) and (- 1, - 5) respectively, then the distance 2AB is equal to

(A)   13 

(B)   26 

(C) 169 

(D) 238

A card is drawn from a well-shuffled deck of 52 playing cards. The probability that the card will not be an ace is 

(A) 1/13

(B) 1/4

(C) 12/13

(D) 3/4