[Type the document title]
Probability-1
Feb. 12
D-579 KAMLA NAGAR AGRA Ph-8287582066
1.
A box contains two white balls, three black balls and four red balls. The number of ways in which
three balls can be drawn from the box so that atleast one of the ball is black is
(A) 20
(B) 64
(C) 84
(D) 74
2.
The probability that any of the men A1,A2 ,A3 ,A 4 is alive after 95 years of age is
1
. The probability
2
that A 1 will die at the age of 95 and will be the first to die is
8
1
(A)
(B)
15
4
15
15
(C)
(D)
64
16
3.
A bag A contains 2 white and 2 red balls and another bag B contanis 4 white 5 red balls. A ball is
drawn and is found to be red. The probability that it was drawn from the bag B is
5
10
(A)
(B)
19
19
1
25
(C)
(D)
2
52
4.
A six faced dice is so blased that it is twice to show an even number as an odd number when
thrown. If it is thrown twice the probability that the sum of two numbers thrown is even is
(A) 1/9
(B) 5/9
(C) 4/9
(D) none of these
5.
Out of the 15 tickets marked with numbers from 1 to 15, three are drawn at random. What is the
chance that the numbers on them are in A.P?
13
9
(A)
(B)
261
39
9
(C)
(D) none of these
15
6.
There of six vertices of a regular hexagon are chosen at random. The possibility that the triangle
with three vertices is equilateral equals
1
1
(A)
(B)
20
10
1
1
(C)
(D)
5
2
7.
n persons sit on a round table . The odd against two spedified persons sitting together is
(A) n  3  : n  1
(B) n  2  : 2
(C) n  1 : 2
8.
(D) 2 : n  3 
The probability of A = probability of B= probability of C 
then P(A+B) is equal
1
(A)
2
37
(C)
64
3
8
5
(D)
8
(B)
1
1
P  AB   P  CB   0 and P  A  B   ,
4
8
[Type the document title]
Probability-1
Feb. 12
D-579 KAMLA NAGAR AGRA Ph-8287582066
a
9.
b
Consider the circuit ,
A
If the probability that each switch is closed is p, then
B
c
find the probability of circuit flowing through AB
(A) p2  p
(B) p3  p  1
(C) p3  p
(D) p2  p  1
10.
From a set of first 18 natural number two number{x,y} are selected randomly then the probabity that
sum of their cubes is divisible by 3; is
1
2
(A)
(B)
5
5
1
1
(C)
(D)
20
10
11.
An ellipse of eccentricity
12.
The probability that at least one of A and B occurs is 0.6. If A and B occur simultaneously with
probability 0.3, then P(A’)+P(B’) =
(A) 0.9
(B) 1.15
(C) 1.1
(D) 1.2
13.
A bag X contains 2 white and 3 black balls and another bag Y contains 4 white and 2 black ball,
One bag is selected at random and a ball is drwan from it . Then the probability for the ball chosen
be white is
2
7
(A)
(B)
15
15
8
14
(C)
(D)
15
15
14.
Bag A contains 4 green and 3 red balls and bagB contains 4 red and 3 green balls. One bag is
taken at random and a ball is drawn and noted it is green. The probability that it comes bagB
(A) 2/7
(B) 2/3
(C) 3/7
(D) 1/3
5
is inscribed in a circle and a point with in the circle is selected at
3
random. The probability that the point lies outside the ellipse is
4
2
(A)
(B)
5
5
1
1
(C)
(D)
3
5
ANSWERS:
1.
B
2.
C
3.
B
4.
B
5.
D
6.
B
7.
A
8.
A
9.
A
10.
B
11.
C
12.
C
13.
C
14.
C
[Type the document title]
Probability-1
Feb. 12
D-579 KAMLA NAGAR AGRA Ph-8287582066