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 2 of 13.
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)
Meena said:
5 years ago
The question is what is the probability of getting "at most" two heads?
Here, at most two heads mean Not more than two heads.
So, HHH is more than two heads. It is not counted in Event. Am I right?
Here, at most two heads mean Not more than two heads.
So, HHH is more than two heads. It is not counted in Event. Am I right?
(6)
Neeraja said:
5 years ago
@ Vivek Rai.
A coin is tossed 3 times. We have 8 possible outcomes. In those 8 possible outcomes, we should choose the outcomes in which we have 1 head, 2 heads or no heads (3tails). But according to you if you consider the only head side of the coin then how did you get 8 in the denominator?
So the answer is 7/8.
A coin is tossed 3 times. We have 8 possible outcomes. In those 8 possible outcomes, we should choose the outcomes in which we have 1 head, 2 heads or no heads (3tails). But according to you if you consider the only head side of the coin then how did you get 8 in the denominator?
So the answer is 7/8.
(5)
Zahid said:
4 years ago
How to find the events of coins quickly like TTT and HHT etc? explain me.
(5)
Sumanth said:
5 years ago
It is 6/8=3/4.
(4)
MUKESH MAHLI said:
4 years ago
At most mean- less than or less than equal to.
Am I right?
Am I right?
(4)
Sowmya said:
1 year ago
The Answer should be 3/8.
(4)
Vivek Rai said:
5 years ago
But it says heads that mean only head should be counted not the tail side of the coin as we know a coin has 2 side head and tail and the question is asking about at most 2 heads so it should be = 3/8.
Anyone, please clarify my doubts.
Anyone, please clarify my doubts.
(3)
Sundar said:
2 decades ago
Hi Guys,
At most two heads means "Total number of HEADs can be 0 to 2".
So we cannot include HHH, because it contains 3 heads.
But we can include TTT, because ZERO head is accepted.
Therefore, the given answers is perfectively correct.
You may ask your doubts here if you have regarding this question?
Have a nice day!
At most two heads means "Total number of HEADs can be 0 to 2".
So we cannot include HHH, because it contains 3 heads.
But we can include TTT, because ZERO head is accepted.
Therefore, the given answers is perfectively correct.
You may ask your doubts here if you have regarding this question?
Have a nice day!
(2)
Tejeshwari said:
3 years ago
Thanks all for explaining it.
(2)
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