The average rate of change in a function from a to b is
.
For the left function, from x = 4 to x = 5, the rate of change is
.
For the right function, the rate of change is
Using a ratio to compare the right function's growth rate with that of the left function, you get .
The right function is growing approximately 21 times faster than the left function (over the interval from 4 to 5).