The probability that a marksman will hit a target is given as $1/5$. Then his probability of at least one hit in $10$ shots is:

Let a biased coin be tossed $5$ times. If the probability of getting $4$ heads is equal to the probability of getting $5$ heads,then the probability of getting at most two heads is

In a box containing $100$ bulbs,$10$ are defective. The probability that out of a sample of $5$ bulbs,none is defective is

$A$ student appeared in an examination consisting of $8$ true-false type questions. The student guesses the answers with equal probability. The smallest value of $n$,so that the probability of guessing at least $n$ correct answers is less than $\frac{1}{2}$,is:

On average, one out of $10$ persons is busy. If $6$ persons are selected at random, then the probability that at least $5$ of them will be busy is...

$A$ die is thrown four times. The probability of getting a perfect square in at least one throw is