-
Soumita Ghosh
- Master | Next Rank: 500 Posts
- Posts: 111
- Joined: Sat Apr 14, 2012 11:09 am
- Thanked: 1 times
- Followed by:7 members
(1) The probability of drawing one blue marble is 6/35 .
(2) The probability of drawing no blue marbles is 4/35 .
What is the probability of drawing at least two blue marbles from a jar if three marbles are chosen?\
A.The probability of drawing one blue marble is .
B.The probability of drawing one blue marble is .
C.BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D.EACH statement ALONE is sufficient.
E.Statements (1) and (2) TOGETHER are NOT sufficient.
OA C
Bu my choice is D
From Statement A:
It is given the probability of drawing blue marble which is 6/35. From here we can find the probability of not drawing blue marble is 1-6/35=29/35
so from here we can find the probability at least two blue marbles from a jar if three marbles are chosen.
6/35*6/35*29/35 + 6/35*6/35*6/35
so statement A is sufficient
From Statement B:
The probability of drawing no blue marbles is 4/35. From here we can find the probability of drawing blue marble which is 1-4/35=31/35
So from here we can find the probability of at least two blue marbles from a jar if three marbles are chosen
So statement B is sufficient.
Therefore each statement is sufficient.
Please explain me where I am wrong!!
(2) The probability of drawing no blue marbles is 4/35 .
What is the probability of drawing at least two blue marbles from a jar if three marbles are chosen?\
A.The probability of drawing one blue marble is .
B.The probability of drawing one blue marble is .
C.BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D.EACH statement ALONE is sufficient.
E.Statements (1) and (2) TOGETHER are NOT sufficient.
OA C
Bu my choice is D
From Statement A:
It is given the probability of drawing blue marble which is 6/35. From here we can find the probability of not drawing blue marble is 1-6/35=29/35
so from here we can find the probability at least two blue marbles from a jar if three marbles are chosen.
6/35*6/35*29/35 + 6/35*6/35*6/35
so statement A is sufficient
From Statement B:
The probability of drawing no blue marbles is 4/35. From here we can find the probability of drawing blue marble which is 1-4/35=31/35
So from here we can find the probability of at least two blue marbles from a jar if three marbles are chosen
So statement B is sufficient.
Therefore each statement is sufficient.
Please explain me where I am wrong!!
