$A$ and $B$ are two events such that $P(A)=0.54$, $P(B)=0.69$ and $P(A \cap B)=0.35.$ Find $P \left( B \cap A ^{\prime}\right)$.
It is given that $P ( A )=0.54$, $P ( B )=0.69$, $P (A \cap B)=0.35$
We know that
$n\left( B \cap A ^{\prime}\right)=n( B )-n( A \cap B )$
$\Rightarrow \frac{n\left( B \cap A ^{\prime}\right)}{n( S )}$ $=\frac{n( B )}{n( S )}-\frac{n( A \cap B )}{n( S )}$
$\therefore P \left( B \cap A ^{\prime}\right)= P ( B )- P ( A \cap B )$
$\therefore P \left( B \cap A ^{\prime}\right)=0.69-0.35=0.34$
If the probability of a horse $A$ winning a race is $1/4$ and the probability of a horse $B$ winning the same race is $1/5$, then the probability that either of them will win the race is
Fill in the blanks in following table :
$P(A)$ | $P(B)$ | $P(A \cap B)$ | $P (A \cup B)$ |
$\frac {1}{3}$ | $\frac {1}{5}$ | $\frac {1}{15}$ | ........ |
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The probability of solving a question by three students are $\frac{1}{2},\,\,\frac{1}{4},\,\,\frac{1}{6}$ respectively. Probability of question is being solved will be
Two balls are drawn at random with replacement from a box containing $10$ black and $8$ red balls. Find the probability that both balls are red.