# 3 red and 4 white balls of different sizes are arranged in a row at random. The probability that no two balls of the same colour are together is

1.  6/35

2.  3/35

3.  1/35

4.  9/35

4

1/35

Explanation :
No Explanation available for this question

# A box X contains 2 white and 3 black balls and another bag Y contains 4 white and 2 black balls. One bag is selected at random and ball is drawn from it. Then the probability for the ball chosen be white is

1.  2/15

2.  7/15

3.  8/15

4.  14/15

4

8/15

Explanation :
No Explanation available for this question

# A box contains 40 balls of the same shape and weight. Among the balls 10 are white, 16 are red and the rest are black, the probability that a ball drawn from the box is not a black is

1.  1/4

2.  2/5

3.  13/20

4.  1/20

4

13/20

Explanation :
No Explanation available for this question

# A bag contains 4 white and 2 black balls. Another contains 3 white and 5 black balls. If one ball is drawn from each, the probability that both are white is

1.  13/24

2.  5/24

3.  1/4

4.  2/14

4

1/4

Explanation :
No Explanation available for this question

# If the two equations x2-cx+d=0 and x2-ax+b=0 have a common root and the second equation has equal roots,then

1.  b+d=ac

2.  2(b+d)=ac

3.  b+d=2ac

4.  (b+d)2=a+c

4

2(b+d)=ac

Explanation :
No Explanation available for this question

# Three balls are drawn from a collection of 7 white, 12 green and 4 red balls. The probability that each is of different colour is

1.

2.

3.

4.

4

Explanation :
No Explanation available for this question

# Three squares of a chess board having 8x8 squares being chosen at random, the chance that all the three are white is

1.  32C3/64C3

2.  8C3/64C3

3.  16C3/64C3

4.  4C3/64C3

4

32C3/64C3

Explanation :
No Explanation available for this question

# In a class 40% of students read History, 25% Civics and 15% both History and Civics. If a student is selected at random from that class, the probability that he reads history, if it is known that he reads Civics is

1.  1/5

2.  2/5

3.  3/5

4.  3/8

4

3/5

Explanation :
No Explanation available for this question

# An experiment yields 3 mutually exclusive and exhaustive events A,B and C. If P(A)=2P(B)=3P(C) then P(A)=

1.  1/11

2.  2/11

3.  23/11

4.  6/11

4

6/11

Explanation :
No Explanation available for this question

1.  3/38

2.  35/33

3.  33/35

4.  1/38

4