Download App

STD 12 - 13. probability — Mathematics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceMathematicsSTD 12 - 13. probability1 Mark
MCQ
A random variable $X$ has the probability distribution  ....For the events $E = \{ X$is prime number $\}$ and $F = \{ X < 4\} $, the probability of $P(E \cup F)$ is
$X$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$
$P(X)$ $0.15$ $0.23$ $0.12$ $0.10$ $0.20$ $0.08$ $0.07$ $0.05$
  • A
    $0.5$
  • ✓
    $0.77$
  • C
    $0.35$
  • D
    $0.87$
✓

Answer

Correct option: B.
$0.77$
b
(b) $E = \{ x$ is a prime number $\}$

$P(E) = P(2) + P(3) + P(5) + P(7) = 0.62,\,$

$F = \{ x < 4\} $, $P(F) = P(1) + P(2) + P(3) = 0.50$

and $P(E \cap F) = P(2) + P(3) = 0.35$

$\therefore $ $P(E \cup F) = P(E) + P(F) - P(E \cap F)$

$= 0.62+0.50 -0.35 = 0.77.$

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

Explore more

More "M.C.Q (1 Marks)" from STD 12 - 13. probability→STD 12 - 13. probability — all question types→Mathematics STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

Let R be a relation on N defined by x + 2y = 8. The domain of R is:
→
The order and degree of the differential equation $\Big(1+3\frac{\text{dy}}{\text{dx}}\Big)^\frac{2}{3}=4\frac{\text{d}^3\text{y}}{\text{dx}^3}$ are:
→
Area between the curve $\text{y}=\cos^2\text{x},x-$axis and ordinates $x = 0$ and $x = p$ in the interval $(0, p)$ is:
→
The integral of $\frac{{{x^2} - x}}{{{x^3} - {x^2} + x - 1}}$ w.r.t. $x$ is 
→
$\frac{\text{d}}{\text{dx}}\Big\{\tan^{-1}\Big(\frac{\cos\text{x}}{1+\sin\text{x}}\Big)\Big\}$ equals:
→
Choose the correct answer from the given four option. The solution of the differential equation $\cos\text{x}\ \sin\text{y}\ \text{dx}+\sin\text{x}\ \cos\text{y}\ \text{dy}=0$ is :
→
What is the degree of differential equation $(y\ ’’’)^2 + (y\ ’’)^3 + (y\ ’)^4 + y^5 = 0?$
→
Area of the figure enclosed by $y = {\cos ^{ - 1}}(\cos \,x),x\, \in \,\left[ {2\pi ,4\pi } \right]$ ; $x-$ axis and $y = {\tan ^{ - 1}}\,x + {\tan ^{ - 1}}\,\frac{1}{x}$ is
→
$\int\frac{\text{dx}}{2\sqrt{\text{x}}(1+\text{x})}=$
→
Let the system of linear equations $4 x+\lambda y+2 z=0$ ;  $2 x-y+z=0$ ;  $\mu x +2 y +3 z =0, \lambda, \mu \in R$ has a non-trivial solution. Then which of the following is true?
→