Answer:

Solution Let's consider the salary of a officer is = 100

Step-by-step explanation:

so , if the salary is increased by 25% then new salary is= 100 25/100 ×100 = 100+25=125

so, his new salary is 125

To make his salary original 25 must be subtracted from 123, then his salary will be 100 or original salary

so,

% decrease = 25 /125×100=1/5×100=20%