Step 1: Read the table for 1981 and 1991.
From the table:
Number of towns/UAs in 1981 = 3,382
Number of towns/UAs in 1991 = 4,652
Step 2: Interpret the question.
The question asks for "the number of towns/UAs during 1981-91". This could mean:
The number at the beginning of the decade (1981): 3,382
The number at the end of the decade (1991): 4,652
The range or the increase during the decade
Based on standard interpretation in such questions, it typically asks for the number at the end of the period or the number during that census year.
Answer: During 1981-91, the number of towns/urban agglomerations increased from 3,382 in 1981 to 4,652 in 1991.