Answer:
The correct option is 4) 0.72.
Step-by-step explanation:
Consider the provided information.
Let us consider that there are 100 members.
(Note: you can take any number the answer will remain the same.)
90% of its members drank protein shakes and of the members who drank protein shakes.
90% of 100 is 90.
Thus, 90 members drank protein shake.
Of the members who drank
protein shakes, 30% took weight-loss medication.
30% of 90 is 27.
That means 27 out of 90 took weight loss medication.
Out of 100 members 90 drank protein shakes that means 10 members does not take protein shakes.
Only 10% of members who did not drink protein shakes took weight-loss medication.
10% of 10 is 1, that means 1 member out of 10 took weight loss medication.
Thus the required table is:
Medication Not Medication Total
Drank shakes 27 63 90
Doesn't Drank shakes 1 9 10
Total 28 72 100
Now we need to find the probability that a gym member does not take weight-loss medication.
72 out of 100 members does not take weight-loss medication.
Therefore, the required probability is: 
Hence, the correct option is 4) 0.72.
