Pat and Kelly went hiking in the mountains. They started at 9,100 ft. They climbed 1,200 ft the first day, descended 900 ft the second day, and climbed 1,000 ft the third day. On the fourth day they descended 800 ft. What was the average altitude at which they hiked?

Answer 1

9,100 + 1,200 + 1,000 - 900 - 800 = ?

Divide the answer by 4.