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A fair coin will be tossed twice
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23 Oct 2019, 23:27
23 Oct 2019, 23:27
00:00
Question Stats:
59% (00:53) correct
40% (00:41) wrong based on 72 sessions
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A fair coin will be tossed twice.
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Quantity A |
Quantity B |
The probability that the coin will NOT land on heads both times |
\(\frac{5}{8}\) |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Re: A fair coin will be tossed twice
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23 Oct 2019, 23:31
23 Oct 2019, 23:31
I have solved the question by this way :
Quantity A means that the coin will be tails on both sides. This means ( 0.5 x 0.5)= 0.25
May someone explains why did I got it wrong and the steps to solve it
Quantity A means that the coin will be tails on both sides. This means ( 0.5 x 0.5)= 0.25
May someone explains why did I got it wrong and the steps to solve it
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Re: A fair coin will be tossed twice
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24 Oct 2019, 07:18
24 Oct 2019, 07:18
4
Asmakan wrote:
A fair coin will be tossed twice.
Quantity A |
Quantity B |
The probability that the coin will NOT land on heads both times |
\(\frac{5}{8}\) |
We can use the complement here.
That is, P(Event A happening) = 1 - P(Event A not happening)
We can rewrite this as: P(Event A not happening) = 1 - P(Event A happening)
So, P(NOT getting two heads) = 1 - P(getting two heads)
P(getting two heads)
P(getting two heads) = P(heads on 1st toss AND heads on 2nd toss)
= P(heads on 1st toss) x P(heads on 2nd toss)
= 1/2 x 1/2
= 1/4
So, P(NOT getting two heads) = 1 - 1/4
= 3/4
We get:
QUANTITY A: 3/4 (aka 6/8)
QUANTITY B: 5/8
Answer: A
Cheers,
Brent
