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What is the probability of flipping a fair coin two times and the coin
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22 Oct 2021, 06:57
22 Oct 2021, 06:57
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What is the probability of flipping a fair coin two times and the coin landing on heads on both flips?
A. 1/8
B. 1/4
C. 1/2
D. 3/8
E. 3/4
A. 1/8
B. 1/4
C. 1/2
D. 3/8
E. 3/4
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Joined: 10 Apr 2015
Posts: 6218
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Re: What is the probability of flipping a fair coin two times and the coin
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22 Oct 2021, 07:14
22 Oct 2021, 07:14
Carcass wrote:
What is the probability of flipping a fair coin two times and the coin landing on heads on both flips?
A. 1/8
B. 1/4
C. 1/2
D. 3/8
E. 3/4
A. 1/8
B. 1/4
C. 1/2
D. 3/8
E. 3/4
Approach #1: Probability rules
P(both heads) = P(1st toss is heads AND 2nd toss is heads)
= P(1st toss is heads) x P(2nd toss is heads)
= 1/2 x 1/2
= 1/4
Answer: B
Approach #2: Counting
P(both heads) = (# of outcomes in which both tosses are heads)/(total # of possible outcomes)
Since there are so few outcomes, let's just list them:
- 1st toss is heads and 2nd toss is heads
- 1st toss is heads and 2nd toss is tails
- 1st toss is tails and 2nd toss is heads
- 1st toss is tails and 2nd toss is tails
total # of possible outcomes = 4
Among those 4 possible outcomes, only 1 outcome meets the condition that both tosses are heads
So, P(both heads) = 1/4
Answer: B
Cheers,
Brent
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Re: What is the probability of flipping a fair coin two times and the coin
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05 Oct 2022, 06:36
05 Oct 2022, 06:36
1
We need to find What is the probability of flipping a fair coin two times and the coin landing on heads on both flips?
Now, there are 4 cases TT, TH, HT, HH
=> Probability that coin will land on head twice = \(\frac{1}{4}\)
So, Answer will be B
Hope it helps!
Watch the following video to learn How to Solve Probability with Coin Toss Problems
Now, there are 4 cases TT, TH, HT, HH
=> Probability that coin will land on head twice = \(\frac{1}{4}\)
So, Answer will be B
Hope it helps!
Watch the following video to learn How to Solve Probability with Coin Toss Problems
