Notice the picture below

you have the center, the h,k, all you really need is the radius "r"
In this question, 10 people average running distance is 2.7miles. Then the sum of their running distance would be: 10 people * 2.7 miles/people= 27 miles.
The group then divided into 2, 4 people with 3 miles average and 6 people with unknown average. Since the people are same like the 10 people group, their total running distance would be the same. The calculation would be:
total distance = group1 * average1 + group2 * average2
27 miles= 4 people * 3 miles/people + 6 people* average2
6 people * average2 = 27 miles -12 miles = 15 miles
average2= 15 miles/6people= 2.5 miles/people
17% of 99 is 16.83. Since that's only the distance it goes in one minute we have to multiply that by 3. 16.83 × 3 = 50.49. Since the elevator is moving down then it will be negative. The answer will be -50.49 meters.