The probability expressed as a percentage of a particular occurrence can never be

In a packet containing $400$ screws,$120$ screws are defective. $A$ screw is picked up randomly from the packet. Then,the probability that the screw picked up is non-defective is .........

An unbiased coin is tossed thrice. Then,the number of total outcomes is ............

Two unbiased dice are thrown once. Write all the possible outcomes of this experiment. What is the probability that the sum of numbers on two dice is $8$?

$A$ card is drawn at random from a well-shuffled pack of $52$ cards. The probability that the card is not a picture card is ...........

In a packet of $500$ screws,$80$ screws are defective. Find the probability that a screw selected at random from the packet is non-defective. (in $/25$)