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Probability — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMathsProbability1 Mark
MCQ
A random variable $X$ has the following probability distribution :
$X$01234567
$P(X)$$a$$6 a$$6 a$$4 a$$8 a$$8 a$$6 a$$9 a$
Find the value of $a$.
  • A
    $\frac{1}{47}$
  • ✓
    $\frac{1}{48}$
  • C
    $\frac{1}{33}$
  • D
    $\frac{1}{29}$
✓

Answer

Correct option: B.
$\frac{1}{48}$
(b) : We know that, $\Sigma P_i=1$
$
\begin{array}{l}
\Rightarrow a+6 a+6 a+4 a+8 a+8 a+6 a+9 a=1 \\
\Rightarrow 48 a=1 \Rightarrow a=\frac{1}{48}
\end{array}
$

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