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A coin is flipped four times. What is the probability of...
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06 Oct 2020, 05:44
06 Oct 2020, 05:44
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52% (01:16) correct
47% (01:15) wrong based on 34 sessions
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A coin is flipped four times. What is the probability of getting heads at least three times?
A. 5/16
B. 1/16
C. 1/4
D. 11/16
E. 3/4
A. 5/16
B. 1/16
C. 1/4
D. 11/16
E. 3/4
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Posts: 6218
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Re: A coin is flipped four times. What is the probability of...
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06 Oct 2020, 06:13
06 Oct 2020, 06:13
1
gagangm wrote:
A coin is flipped four times. What is the probability of getting heads at least three times?
A. 5/16
B. 1/16
C. 1/4
D. 11/16
E. 3/4
A. 5/16
B. 1/16
C. 1/4
D. 11/16
E. 3/4
Let's solve this question using counting techniques
Always start with the denominator (the total number of possible outcomes)
The 1st coin can have 2 outcomes (heads or tails)
The 2nd coin can have 2 outcomes (heads or tails)
The 3rd coin can have 2 outcomes (heads or tails)
The 4th coin can have 2 outcomes (heads or tails)
So the TOTAL number of outcomes = (2)(2)(2)(2) = 16
Getting heads at least three times = getting exactly three heads OR getting exactly four heads
Getting exactly three heads
There are 4 ways to accomplish this: THHH, HTHH, HHTH, HHHT
Getting exactly three heads
There is 1 way to accomplish this: HHHH
TOTAL number of ways to get at least three heads = 4 + 1 = 5
P(get heads at least three times) = 5/16
Answer: A
Cheers,
Brent
Re: A coin is flipped four times. What is the probability of...
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06 Oct 2020, 07:03
06 Oct 2020, 07:03
1
4C3+4C4/16
5/16
À
Posted from my mobile device
5/16
À
Posted from my mobile device
