Final answer:
The order of the three people in terms of the time spent walking from least to greatest is Beth, Cindy, Ari.
Step-by-step explanation:
To determine the order of the three people in terms of the time spent walking, we need to convert all the time intervals to the same unit.
Let's start by converting Ari's time from hours to minutes: 2 3/4 hours = 2.75 * 60 = 165 minutes. Beth's time is already in minutes.
Now let's convert Cindy's time from hours and minutes to minutes: 1 hour = 60 minutes; 21 minutes. So, Cindy's total time is 60 + 21 = 81 minutes.
From least to greatest time spent walking, the order is: Beth, Cindy, Ari.