Number of white chips = 4 Number of black chips = 6 Total number of chips = 4 + 6 = 10 Choosing the first white chip: p(white chip) = 4/10 = 2/5
Now the numbers are: Number of white chips = 3 Number of black chips = 6 Total number of chips = 3 + 6 = Choosing the second white chip: p(white chip) = 3/9 = 1/3
p(white chip followed by white chip) = 2/5 * 1/3 = 2/15