Question

A bag contains 5 blue balls and 7 white balls find the probability of not getting a blue ball

Answer 1

Given

$\bold{Total \ number \ of \ blue \ balls} = 5$

$\bold{Total \ number \ of \ white \ balls} = 7$

$\bold{Total \ number \ of \ balls} = 5+7=12$

                                                                                             

SOMETHING YOU NEED TO KNOW

$\sf Probability \ of \ an \ outcome = \dfrac{Given \ outcome}{total \ no: \ of \ outcomes}$

$\sf Probability \ of \ not \ getting \ an \ outcome =1- \dfrac{Given \ outcome}{total \ no: \ of \ outcomes}$

                                                                       

$\implies \sf Probability \ of \ not \ getting \ a \ blue \ ball$

$=1- \dfrac{5}{12}$

$= \dfrac{12-5}{12}$

$= \dfrac{7}{12}$

$\boxed{\boxed{\bold{Therefore, \ the \ probability \ of \ not \ getting \ a \blue \ ball \ is \ \frac{7}{12}}}}}}}$

                                                             

Answer 2

SolutioN :

Let,

• The Total number of blue balls = 5.
• And Total number of white balls = 7.
• Total number of balls bag contains = 12.

ConcepT :

$\tt \bigstar \: Probability \: of \: any \: event \: is \: always$

$\tt \: \: \: \: \: \: \: \: \: \: \: \: \: 0 \leqslant \: Probability \: \leqslant 1.$

So, We can say that Sum of any given probability ( P ) is must be equal to 1.

$\rule{100}2$

$\tt \dagger \: \: \: \: \: Probability \: of \: an \: event = \dfrac{ Number \: of \: favorable \: Outcome }{Total \: number \: of \: Outcome}$

$\tt \longmapsto P = \dfrac{5}{12}$

☯ Let's Find Probability of not getting a blue ball.

$\tt \longmapsto 1 - \dfrac{5}{12}$

$\tt \longmapsto \dfrac{12 - 5}{12}$

$\tt \longmapsto \dfrac{7}{12}$

Therefore, the probability of not getting a blue ball is 7 / 12.

$\rule{200}3$

VerificatioN :

→ 1 = 7 / 12 + 5 / 12

→ 1 = 12 / 12.

→ 1 = 1.

★ Hence Verify.