9. A box contains red and identical white balls. Two balls are drawn at random in succession without replacement. Write the sample space for this experiment.
Given, Number of red balls =1
Number of white balls = 3
Let R denote the event that the red ball is drawn.
And W denotes the event that a white ball is drawn.
Since two balls are drawn at random in succession without replacement,
if the first ball is red, the second ball will be white. And if the first ball is white, second can be either of red and white
The required sample space is:
S = {RW, WR, WW}