An unbiased coin is tossed | Probability | JEE MAIN 2020

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JEE MAIN 2020

07-01-20 S1

Question

An unbiased coin is tossed 5 times. Suppose that a variable X is assigned the value k when k consecutive heads are obtained for k = 3, 4, 5, otherwise X takes the value –1. Then the expected value of X, is

Select the correct option:

A

$\frac{3}{16}$

B

$-\frac{1}{8}$

C

$-\frac{3}{16}$

D

$\frac{1}{8}$

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