Probability question
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Carlo75
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I think:
The probability to get tails at the first and second tosses is 1/4 (1/2*1/2) - TT
The probability to get heads at the last tree tosses is 1/8 (1/2*1/2*1/2) - HHH
The probability to get TTHHH is 1/4*1/8 = 1/32
the prop to get exactly 2 tails in 5 tosses is 1/32*2C5 = 1/32*(5!/2!*3!) =>1/32 * (5*4/2) = 5/16
but I am in doubt, please could somebody confirm that?
The probability to get tails at the first and second tosses is 1/4 (1/2*1/2) - TT
The probability to get heads at the last tree tosses is 1/8 (1/2*1/2*1/2) - HHH
The probability to get TTHHH is 1/4*1/8 = 1/32
the prop to get exactly 2 tails in 5 tosses is 1/32*2C5 = 1/32*(5!/2!*3!) =>1/32 * (5*4/2) = 5/16
but I am in doubt, please could somebody confirm that?
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egybs
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You missed a few:
HTHTH, HTTHH, HHTTH. So total is 10/32 = 5/16
HTHTH, HTTHH, HHTTH. So total is 10/32 = 5/16
aatech wrote:These are the possible ways of getting 2 tails
HHHTT, HHTHT, HTHHT, THHHT, THHTH, THTHH, TTHHH = 7 ways
Total ways of getting head or tail = 32
So, prob = 7/32. IMO
