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}.
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n(E) | = | 7 | . |
n(S) | 8 |
Discussion:
120 comments Page 1 of 12.
Sundar said:
1 decade 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!
(1)
Malarvizhi said:
1 decade ago
How did say n(s) is 8?
Sundar said:
1 decade ago
@Malarvizhi
Note: "At most two heads" --(means)--> Not more than two heads.
Here S = {TTT, TTH, THT, HTT, THH, HTH, HHT, HHH} <--- (8 combinations)
Therefore, n(S) = 8.
Note: "At most two heads" --(means)--> Not more than two heads.
Here S = {TTT, TTH, THT, HTT, THH, HTH, HHT, HHH} <--- (8 combinations)
Therefore, n(S) = 8.
Abhijit said:
1 decade ago
Total no of probabilities= 2^3 =8
for 2/1/0 heads probability is =7(only 1 left HHH)
for 2/1/0 heads probability is =7(only 1 left HHH)
Dharini said:
1 decade ago
I cant follow what abhijit said why it is 2 power 3?
Murugesh said:
1 decade ago
@dharini...
2---> H & T
3---> total no of coins.
so 2^3.
2---> H & T
3---> total no of coins.
so 2^3.
Dinesh said:
1 decade ago
Got it murugesh
thanks..
thanks..
SATHYA said:
1 decade ago
What is unbiased coins?
Sathish said:
1 decade ago
Thank you sundar.
Sara said:
1 decade ago
Won't it be 3 out of 8?
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