Answer:
If someone get a 150% salary raise, it means that the current salary will be increased by 1.5 (150/100) from the current amount.
To demonstrate this, let's assume that someone's salary is $1000, if we increase it by 150% we must calculate 150% of $1000.

150% of $1000 is $1500, since the person wll get a 150% salary raise, it means that the actual salary INCREASES that value, the final salary of a person will be:
Final salary = previous salary + amount of increase
Final salary = $1000 + $1500
Final salary = $2500