A's monthly income = Rs 450

A's monthly increment = Rs 25/12

B's monthly income = Rs 600

B's monthly increment = Rs 20/12

Let A requires ' x ' month to have A's salary to be equal to B's salary so,

450+25/12+x=600+20/12

X=12.465 years . After 12.465 yrs A's sal becomes more than B's sal....