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 5 of 13.
Sam said:
7 years ago
The condition is atmost 2 heads how TTT is possible?
SHIVU said:
7 years ago
Thanks for your answer @Sundar.
Taz said:
7 years ago
Very clear explanation. Thank you @Sundar.
Soaib said:
8 years ago
Thanks @Harini.
Krishna said:
8 years ago
Can someone help me to solve this?
If head appears consecutively in the first three tosses of a fair/unbiased coin. What is a probability of Head appearing in the fourth toss also?
If head appears consecutively in the first three tosses of a fair/unbiased coin. What is a probability of Head appearing in the fourth toss also?
Akhil said:
8 years ago
@Belle.
A. P(All boys) = (1/2)^3 = 1/8.
B. P(All girls or all boys) = 1/8 + 1/8 = 1/4.
C. P(Exactly two boys or two girls) = 2*3C2(1/2)^2*(1/2) = 2*3*(1/8) = 3/4(here we need 2 of particular gender. So., if we calculate[2*3C2(1/2)^2] we'll get 2 of particular gender and then this should be multiplied with 1/2. Atlast we get 3/4).
D. P(At least one child of each gender) = 1 -P(all girls or all boys)= 1 - 1/4 = 3/4.
I hope this helps.
A. P(All boys) = (1/2)^3 = 1/8.
B. P(All girls or all boys) = 1/8 + 1/8 = 1/4.
C. P(Exactly two boys or two girls) = 2*3C2(1/2)^2*(1/2) = 2*3*(1/8) = 3/4(here we need 2 of particular gender. So., if we calculate[2*3C2(1/2)^2] we'll get 2 of particular gender and then this should be multiplied with 1/2. Atlast we get 3/4).
D. P(At least one child of each gender) = 1 -P(all girls or all boys)= 1 - 1/4 = 3/4.
I hope this helps.
Belle said:
8 years ago
Hi, can anyone solve this?
A couple has 3 children. Find each probability:
a. All boys.
b. All girls and boys.
c. Exactly 2 boys or 2 girls.
d. At least 1 child of each gender.
A couple has 3 children. Find each probability:
a. All boys.
b. All girls and boys.
c. Exactly 2 boys or 2 girls.
d. At least 1 child of each gender.
Shaikh Sayma said:
8 years ago
What is the Probability of getting at the most 2 tails?
Shubham said:
8 years ago
Thanks @Harini.
Deva said:
8 years ago
Thank You @SUNDAR.
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