Question

A bag contains 12 coloured balls. Five of the balls are red and the rest are blue. A ball is drawn at random from the bag. It is then replaced and a second ball is drawn. Th e colour of each ball is recorded. a List the possible outcomes of the experiment. b Calculate the probability that: i the fi rst ball is blue ii the second ball is red iii the fi rst ball is blue and the second ball is red iv the two balls are the same colour v the two balls are a diff erent colour vi neither ball is red vii at least one ball is red.

Answer 1

A bag contains 12 blue balls and x red balls. if one ball is drawn at random (i)what is the probability that it will be red balls,(ii)if 8 more red balls are put in the bag,and if the probability of drawing a red ball will be twice that of the probability in

(i),then find x