Exponential - Percent of Increase and Decrease

Question

For the exponential function A = 81*1.38^x, what is the percent of Increase?

For the exponential function A = 0.52*86.0^x, what is the percent of decrease?

Answer 1

Percent increase = [(81*1.38^x - 81)/81]*100%, positive for values of x > 0

Percent decrease = [(0.52-0.52*86.0^x)/0.52]*100%, positive for values of x < 0

Answer 2

1.38 = 138% = 100% + 38% , so the percent increase is 38%

86 = 8600% = 100% + 8500% , so the percent increase is 8500%

Are you sure it is no 0.52 * 0.86^x ?????

\ in that case, it is 0.86 = 86% = 100% - 14% , it is 14% decrease