Aptitude - Probability - Discussion
Discussion Forum : Probability - General Questions (Q.No. 2)
2.
A bag contains 2 red, 3 green and 2 blue balls. Two balls are drawn at random. What is the probability that none of the balls drawn is blue?
Answer: Option
Explanation:
Total number of balls = (2 + 3 + 2) = 7.
Let S be the sample space.
| Then, n(S) | = Number of ways of drawing 2 balls out of 7 | |||
| = 7C2 ` | ||||
|
||||
| = 21. |
Let E = Event of drawing 2 balls, none of which is blue.
 n(E) |
= Number of ways of drawing 2 balls out of (2 + 3) balls. | |||
| = 5C2 | ||||
|
||||
| = 10. |
| P(E) = |
n(E) | = | 10 | . |
| n(S) | 21 |
Discussion:
116 comments Page 12 of 12.
Rizwan said:
9 years ago
Why not the answer is 5/7?
ASHUTOSH said:
9 years ago
Why not the answer is 5/7?
Manish Kumar Gupta said:
7 years ago
How come this 2c2/7c2?
Amor said:
9 years ago
Agree with you @Roma.
Srija said:
1 decade ago
You are right akash!
Gmbvbgmkgh said:
10 years ago
Why is E used?
Post your comments here:
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