A group of 10 people ran an average of 2.7 miles in one week. if the first 4 people in the group averaged 3 miles, what did the last 6 people average

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