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:
122 comments Page 1 of 13.
Abdul Wahab said:
2 weeks ago
We can answer this question by using the Binomial Distribution.
3 x 1/4 x 1/2 = 3/8.
3 x 1/4 x 1/2 = 3/8.
Gech said:
8 months ago
It must be 3\8.
(10)
Chinmay Gawane said:
1 year ago
3/8 is the right answer.
(20)
Reena said:
2 years ago
At most 2 heads means it cannot be more than 2. It can be zero or 1 or 2 but not 3. And there is only one case that have 3 (HHH). So probability is 7/8.
(54)
Ragini said:
2 years ago
The right Answer is 3/8.
(12)
Ismail said:
2 years ago
"At most 2 head" means a maximum 2 no. of heads that is there can be 0 heads,1 head or 2 heads.
So, TTT, TTH, THT, THH, HTT, HHT, HTH have at most 2 heads.
So, n(E)=7 & n(S)= 8 ---> n(E)/n(S) = 7/8.
So, TTT, TTH, THT, THH, HTT, HHT, HTH have at most 2 heads.
So, n(E)=7 & n(S)= 8 ---> n(E)/n(S) = 7/8.
(14)
Sowmya said:
2 years ago
The Answer should be 3/8.
(5)
Manisha Yadav said:
2 years ago
The right answer should be 3/8.
(15)
Chelsia said:
2 years ago
We can get quickly the number of events like 2 to the Power of (number of coins).
I.e 2'3=> 8.
I.e 2'3=> 8.
(7)
Asmi said:
2 years ago
At most means not more than 2 heads.
And at least means more than 2 heads.
And at least means more than 2 heads.
(24)
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