With her promotion, Nicki's salary increased from $19.50 an hour to $22.50 an hour. What is the percent of increase, rounded to the nearest whole number?
A. 9%
B. 15%
C. 18%
D. 22%
The equation for percentage increase is {(New value - old value) / old value} x100% Therefore it should be {(22.5 - 19.5) / 19.5} x 100% =15% (rounded to nearest whole number) Answer is B