When a balanced die is rolled,the probability of getting a multiple of $3$ on it is $\ldots \ldots \ldots .$

In a carton of $20$ bulbs,$4$ bulbs are defective. Find the probability that a bulb selected at random is non-defective.

An unbiased coin is tossed thrice. The probability of getting a tail all three times is ...........

$A$ lot consists of $48$ mobile phones of which $42$ are good,$3$ have only minor defects,and $3$ have major defects. Varnika will buy a phone if it is good,but the trader will only buy a mobile if it has no major defect. One phone is selected at random from the lot. What is the probability that it is
$(i)$ acceptable to Varnika?
$(ii)$ acceptable to the trader?

In any situation that has only two possible outcomes,each outcome will have a probability of $\frac{1}{2}$. True or false? Why?

Chits numbered from $1$ to $120$ are put in a box and a chit is drawn randomly from the box. The probability that the chit drawn bears a $3$-digit number is ............