Question 363860
a = 150 meters
r = .94 (6% lower)
n = 15 

S = travel distance of balloon in 15 mins

S = a (1-r^n)/ (1-r)
  = 150 (1-.94^15) / (1-.94)
  = 150 (10.07847
  = 1511.8

The balloon travels 1511.8 meters in 15 mins.