A bag contains $3$ red and $7$ black balls, two balls are taken out at random, without replacement. If the first ball taken out is red, then what is the probability that the second taken out ball is also red
$\frac{1}{{10}}$
$\frac{1}{{15}}$
$\frac{3}{{10}}$
$\frac{2}{{21}}$
Three coins are tossed once. Find the probability of getting exactly $2$ tails.
If in a lottary there are $5$ prizes and $20$ blanks, then the probability of getting a prize is
Two dice are thrown. The events $A,\, B$ and $C$ are as follows:
$A:$ getting an even number on the first die.
$B:$ getting an odd number on the first die.
$C:$ getting the sum of the numbers on the dice $\leq 5$
State true or false $:$ (give reason for your answer)
Statement : $A$ and $B$ are mutually exclusive
Seven chits are numbered $1$ to $7$. Three are drawn one by one with replacement. The probability that the least number on any selected chit is $5$, is
If $P(A) = 0.65,\,\,P(B) = 0.15,$ then $P(\bar A) + P(\bar B) = $