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Probability questions??

Three coins are tossed IN SUCCESSION. What is the probability of heads-tails-heads?
1/2
1/6
1/8

Three coins are tossed AT ONCE. What is the probability of two heads and one tail?
1/8
3/8
1/512

User Derekahc
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2 Answers

3 votes

the correct answer to question 1 is 1/8

User I Bowyer
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1 vote

Answer:

Ques 1)

The probability of heads-tails-heads is:

1/8

Ques 2)

The probability of two heads and one tail is:

3/8

Explanation:

Ques 1)

When three coins are tossed in succession(i.e. one after the other)

Then the events are independent.

Since the happening of one event do not effect the other.

Hence, the probability of heads-tails-heads is:


=(1)/(2)* (1)/(2)* (1)/(2)\\\\\\=(1)/(2^3)\\\\\\=(1)/(8)

Hence, probability is: 1/8

Ques 2)

When three coins are tossed together than the sample space is as follows:

{HHH , HHT , HTH , THH , TTT , TTH , HTT , THT}

There are a total of 8 outcomes.

Also, the number of outcomes that have two heads and one tail are: 3

Since the outcomes are: { HHT , THH , HTH }

Hence, the probability of two head and one tail is: 3/8

User Prasanth Bendra
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