Let the total income of the person for the year be \( I \).
- The total expenditure for the first 5 months is:
\[
5 \times 50,000 = 250,000
\]
- The total expenditure for the next 7 months is:
\[
7 \times 54,000 = 378,000
\]
Thus, the total expenditure for the year is:
\[
250,000 + 378,000 = 628,000
\]
The person saved ₹ 23,000 during the year, so the total income is:
\[
I = 628,000 + 23,000 = 651,000
\]
The average monthly income is:
\[
\text{Average Income} = \frac{651,000}{12} = 54,250
\]
Thus, the average monthly income is ₹ 54,250.