$A$ bag contains $5$ red balls and some blue balls. If the probability of drawing a blue ball is double that of a red ball,determine the number of blue balls in the bag.

Five cards - the ten,jack,queen,king and ace of diamonds,are well-shuffled with their face downwards. One card is then picked up at random.
$(i)$ What is the probability that the card is the queen?
$(ii)$ If the queen is drawn and put aside,what is the probability that the second card picked up is $(a)$ an $ace?$ $(b)$ a $queen?$

Three unbiased coins are tossed simultaneously. Then,the probability of receiving at least two heads 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 $4$?

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

$A$ carton consists of $100$ shirts of which $88$ are good,$8$ have minor defects and $4$ have major defects. Jimmy,a trader,will only accept the shirts which are good,but Sujatha,another trader,will only reject the shirts which have major defects. One shirt is drawn at random from the carton. What is the probability that
$(i)$ it is acceptable to Jimmy? $\quad (ii)$ it is acceptable to Sujatha?