Consecutively marked number of houses are 1, 2, 3, 4 …… 47, 48, 49.
x is such number so that sum of one side of x numbers = sum of other side number of x d in all the terms of series = 1.
then sum of number from 1 to x – 1, (a) = 12, n = x – 1.
and sum of numbers from x + 1 to 49
Then according to question,
Hence, value of x is 35.