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Probability question

2023 · 13 Apr · Shift 1 · Q28

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JEE Main
Mathematics
Probability
2023 · 13 Apr · Shift 1 · Q28

Probability question

2023 · 13 Apr · Shift 1 · Q28

JEE MainMathematicsProbabilityMCQ+4 / −1

A coin is biased so that the head is 3 times as likely to occur as tail. This coin is tossed until a head or three tails occur. If

\mathrm{X}

denotes the number of tosses of the coin, then the mean of

\mathrm{X}

is :

A
$\frac{81}{64}$
B
$\frac{37}{16}$
C
$\frac{21}{16}$
D
$\frac{15}{16}$

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