MCQ
For a biased die the probabilities for different faces to turn up are given below

$Face:$ $1$ $2$ $3$ $4$ $5$ $6$
$Probability:$ $0.1$ $0.32$ $0.21$ $0.15$ $0.05$ $0.17$

The die is tossed and you are told that either face $1$ or $2$ has turned up. Then the probability that it is face $1$, is

  • $\frac{5}{{21}}$
  • B
    $\frac{5}{{22}}$
  • C
    $\frac{4}{{21}}$
  • D
    None of these

Answer

Correct option: A.
$\frac{5}{{21}}$
a
(a) Required probability $ = \frac{{0.1}}{{0.1 + 0.32}} = \frac{{0.1}}{{0.42}} = \frac{5}{{21}}.$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

A random variable has the following probability distribution:
$X = x_i$ $0$ $1$ $2$ $3$ $4$ $5$ $6$ $7$
$P(X = X_i)$ $0$ $2p$ $2p$ $3p$ $p^2$ $2p^2$ $7p^2$ $2p$
If $A=\left|\begin{array}{lll}1 & 1 & 1 \\ 1 & 1 & 1 \\ 1 & 1 & 1\end{array}\right|,$ then $A^2$ is:
If $P$ is a $3 \times 3$ matrix such that $P^{\top}=2 P+I$, where $P^{\top}$ is the transpose of $P$ and $I$ is the $3 \times 3$ identity matrix, then there exists a column matrix $X=\left[\begin{array}{l}x \\ y \\ z\end{array}\right] \neq\left[\begin{array}{l}0 \\ 0 \\ 0\end{array}\right]$ such that 
If ${\cot ^{ - 1}}\frac{n}{\pi } > \frac{\pi }{6},\,\,n \in N$ , then the maximum  value of $n$ is
The area (in sq. units) of the region $A\,\, = \,\left\{ {\left( {x\,,\,y} \right)\,:\,{x^2}\, \le \,y\, \le \,x + 2} \right\}$ is
If $\left[ {a \times b\;\;b \times c\;\;c \times a} \right] = \alpha \;{\left[ {a\;\;b\;\;c} \right]^2}$ then $\lambda$ is equal to 
In a $\Delta ABC,$ if $\left| {\,\begin{array}{*{20}{c}}1&a&b\\1&c&a\\1&b&c\end{array}\,} \right| = 0$, then ${\sin ^2}A + {\sin ^2}B + {\sin ^2}C = $
Let $p$ and $p+2$ be prime numbers and let $\Delta=\left|\begin{array}{ccc}p ! & (p+1) ! & (p+2) ! \\ (p+1) ! & (p+2) ! & (p+3) ! \\ (p+2) ! & (p+3) ! & (p+4) !\end{array}\right|$ Then the sum of the maximum values of $\alpha$ and $\beta$, such that $p ^{\alpha}$ and $( p +2)^{\beta}$ divide $\Delta$, is $........$
Time period is a:
The inverse of the function $\frac{{{{10}^x} - {{10}^{ - x}}}}{{{{10}^x} + {{10}^{ - x}}}}$ is