9
Q:

# A bag contains 12 white and 18 black balls. Two balls are drawn in succession without replacement. What is the probability that first is white and second is black?

 A) 6/145 B) 36/145 C) 18/95 D) 12/145

Explanation:
 The probability that first ball is white: =C112C130=1230=25 Since, the ball is not replaced; hence the number of balls left in bag is 29. Hence the probability the second ball is black:=C118C129=1829 Required probability =(25)×(1829) =36/145
Q:

If in a two digit number, the digit at unit place is y and the digit at tens place is 5, then the number is

 A) 50y + y B) 5y + 5 C) 50 + y D) 50y + 5

Explanation:

0 5
Q:

What is the value of sin ­7π/4c?

 A) ­1/√2 B) 2/√3 C) 1/√2 D) ­2/√3

Explanation:

0 0
Q:

√(cosec$2$ -­ 1)/cosecA is equal to?

 A) cosA B) sinA C) cosecA D) secA

Explanation:

0 2
Q:

Find measure of central angle of the sector whose perimeter is 25 cm and radius of the circle is 7 cm?

 A) 45° B) 22.5° C) 135° D) 90°

Explanation:

0 2
Q:

­ What is the equation of the line if its slope is 3/4 and y­intercept is 5?

 A) 3x + 4y = ­-20 B) 3x + 4y = 20 C) 3x ­- 4y = ­-20 D) 3x ­- 4y = 20

Explanation:

0 1
Q:

If  and , then the values of r and $θ$ are: $(0°⩽θ≤90°)$

 A) r=1, θ=30° B) r=1⁄2, θ=30° C) r=3 , θ=30° D) r=2, θ=60°

Explanation:

0 0
Q:

If the simple interest on a sum of money for 2 years at 5% per annum is Rs. 50, the compound interest on the same at the same rate and for the same time is:­

 A) Rs. 50.50 B) Rs. 51.25 C) Rs. 51.50 D) Rs. 50.05

Explanation:

0 0
Q:

If the length of the shadow of a vertical pole be √3 times the height of the pole, the angle of elevation of the sun is:­

 A) 60° B) 45° C) 30° D) 90°