The probability of taking each color is 14/81
Probability is the likelihood for an event to occur. The certainty for an event to occur is 1 which is equivalent to 100%.
Probability is expressed as
probability = sample space / total outcome
total outcome = 9
Probability of selecting green = 7/9
probability of selecting blue counter = 2/9
Probability of selecting two counters of different color = 7/9 × 2/9
= 14/81
Therefore, the probability that Ria takes one counter of each colour is 14/81