Aptitude - Probability - Discussion
Discussion Forum : Probability - General Questions (Q.No. 5)
5.
Three unbiased coins are tossed. What is the probability of getting at most two heads?
Answer: Option
Explanation:
Here S = {TTT, TTH, THT, HTT, THH, HTH, HHT, HHH}
Let E = event of getting at most two heads.
Then E = {TTT, TTH, THT, HTT, THH, HTH, HHT}.
 P(E) = |
n(E) | = | 7 | . |
| n(S) | 8 |
Discussion:
121 comments Page 8 of 13.
Ankush said:
10 years ago
Atleast two tails means?
Yadlapalli sivateja said:
10 years ago
To HHH condition:
H (1/2).
H (1/2)+3!/3! = 1/8.
H (1/2) answer = 1/8+3/8 = 1/2.
To TTH condition:
T(1/2).
T(1/2)+3!/2! = 3/8.
T (1/2).
H (1/2).
H (1/2)+3!/3! = 1/8.
H (1/2) answer = 1/8+3/8 = 1/2.
To TTH condition:
T(1/2).
T(1/2)+3!/2! = 3/8.
T (1/2).
Namgay said:
10 years ago
We know there are 8 combinations but What is the trick to get the combinations when we toss three coins like HHH TTH?
Venkatesh said:
10 years ago
Why to consider the THT, TTH, HTT, TTT?
Pratyush said:
10 years ago
At-most 2 means its 0, 1, or 2.
Rishal said:
10 years ago
What is n(s)?
Trusha said:
10 years ago
Hi guys I'm totally confused about 'or' and 'and' concept can anyone help please?
Mohan said:
10 years ago
TTT there is no heads then why we consider that.
Nandhini said:
10 years ago
Guys I am confused about atleast and atmost. Can anyone give me a correct idea about that. I thought atleast 2 heads means we can have 2 heads and more than 2.
According to that we get 7/8. Then how do you get 7/8 for atmost 2 heads?
According to that we get 7/8. Then how do you get 7/8 for atmost 2 heads?
Kishore said:
10 years ago
If the meaning of unbiased coin is different coins then the answer is correct.
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