Let B1W2 denote the outcome that the first ball drawn is B1 and the second ball drawn is W2. Because the first ball is replaced
before the second ball is drawn, the outcomes of the experiment are equally likely. List all 25 possible outcomes of the experiment on a sheet of paper.Consider the event that the first ball that is drawn is blue.
Supplementary angles sum up to 180°, suppose the supplement of 161° is x. Then 161+x=180 solving for x we subtract 161 from both sides 161-161+x=180-161 x=19 thus the supplement is 19°