If you would like to know the change in Debra's hours, you can calculate this using the following steps:
x% of 16 hours is 22 hours
x% * 16 = 22
x/100 * 16 = 22
x = 22 * 100 / 16
x = 137.5%
137.5% - 100% = 37.5%
22 hours - 16 hours = 6 hours
The correct result would be: an increase of 6 hours, and an increase of 37.5%.