Answer:
39.1 minutes
Step-by-step explanation:
Given that:
Current wait time = 34 minutes
Current wait time is 15% shorter than average wait time when study started.
Average wait time when study started :
15% of current wait time :
0.15 * 34
= 5.1 minutes
Average wait time when study started :
34 minutes + 5.1 minutes
= 39.1 minutes