The monthly salaries of A and B together amount to ₹45,000. A spends 75% of his salary and B spends 80% of his salary. If now their savings are the same, then the salary of B (in ₹) is:

Let the salary of A be ₹S
A
​
and the salary of B be ₹S
B
​
.
Given:

S
A
​
+S
B
​
=45000
A spends 75% of his salary, so A's savings are:

Savings of A=(100%−75%) of S
A
​
=25% of S
A
​

B spends 80% of his salary, so B's savings are:

Savings of B=(100%−80%) of S
B
​
=20% of S
B
​

Since their savings are the same:

25% of S
A
​
=20% of S
B
​

25⋅S
A
​
=20⋅S
B
​

S
B
​

S
A
​

​
=
25
20
​
=
5
4
​

Thus, the ratio of the salaries of A and B is 4:5.
The salary of B is given by:

S
B
​
=
4+5
5
​
×45000=
9
5
​
×45000=5×5000=₹25,000