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On one side of a coin there is the number 0 and on the other side the
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07 Oct 2021, 09:31
07 Oct 2021, 09:31
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On one side of a coin there is the number 0 and on the other side the number 1. What is the probability that the sum of three coin tosses will be 2?
A. 1/8.
B. 1/2.
C. 1/5.
D. 3/8.
E. 1/3.
A. 1/8.
B. 1/2.
C. 1/5.
D. 3/8.
E. 1/3.
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Joined: 10 Apr 2015
Posts: 6218
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Re: On one side of a coin there is the number 0 and on the other side the
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07 Oct 2021, 10:47
07 Oct 2021, 10:47
1
Carcass wrote:
On one side of a coin there is the number 0 and on the other side the number 1. What is the probability that the sum of three coin tosses will be 2?
A. 1/8.
B. 1/2.
C. 1/5.
D. 3/8.
E. 1/3.
A. 1/8.
B. 1/2.
C. 1/5.
D. 3/8.
E. 1/3.
Let's examine ONE CASE in which we get a sum of 2.
How about getting 0 then 1 then 1
Now let's determine the probability of this one case.
P(getting 0 then 1 then 1) = P(1st toss is 0 AND 2nd toss is 1 AND 3rd toss is 1)
= P(1st toss is 0) AND P(2nd toss is 1) AND P(3rd toss is 1)
= 1/2 x 1/2 x 1/2
= 1/8
Of course, we've only examined ONE CASE so far.
Now consider the fact, that we can arrange one 0 and two 1's in 3 different ways: {0, 1, 1}, {1, 0, 1} and {1, 1, 0}
Each of these 3 possibilities is equally likely.
So, P(sum is 2) = (1/8)(3)
= 3/8
Answer: D
General Discussion
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Re: On one side of a coin there is the number 0 and on the other side the
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18 Oct 2022, 09:53
18 Oct 2022, 09:53
1
Given that On one side of a coin there is the number 0 and on the other side the number 1. We need to find What is the probability that the sum of three coin tosses will be 2?
As the coin is tossed 3 times => Number of cases = \(2^3\) = 8 cases
Sum of the three tosses is 2. So following are the possible outcomes
(0, 1, 1), (1, 0, 1), (1, 1, 0)
=> 3 cases
=> Probability that the sum of three coin tosses will be 2 = \(\frac{3}{8}\)
So, Answer will be D
Hope it helps!
The Concept is similar to that of Rolling a dice. Watch the following video to learn How to Solve Dice Rolling Probability Problems
As the coin is tossed 3 times => Number of cases = \(2^3\) = 8 cases
Sum of the three tosses is 2. So following are the possible outcomes
(0, 1, 1), (1, 0, 1), (1, 1, 0)
=> 3 cases
=> Probability that the sum of three coin tosses will be 2 = \(\frac{3}{8}\)
So, Answer will be D
Hope it helps!
The Concept is similar to that of Rolling a dice. Watch the following video to learn How to Solve Dice Rolling Probability Problems
