Probability of Significant Decrease in Blood Pressure

A team of researchers is studying the effects of a new medication on blood pressure. They conduct a trial with 200 participants, of which 120 received the medication and 80 received a placebo.

After a month of treatment, they observe the following outcomes:

• For the medication group, 90 out of 120 participants showed a significant decrease in blood pressure.
• For the placebo group, 20 out of 80 participants showed a significant decrease in blood pressure.

Based on these results, calculate the probability that a randomly selected participant from all the participants showed a significant decrease in blood pressure. Provide your answer as a simplified fraction.