We may observe that the given data be maximum class frequency is 40 belonging to 1500- 2000 intervals
So,
modal class = 1500- 2000
l=1500, f=40, f0=24, f2=33, h=50
Mode = \(I+(\frac{f-f_0}{2f-f_0-f_2})h\)
\(=1500+(\frac{40-24}{2(40)-24-33})50\)
=1500 + 347.826
=1847.826
So,
modal class monthly expenditure was Rs. 1847.83
We may compute class marks (xi) as per the relation:
xi \(=\frac{upper\,class\,limit+lower\,class\,limit}{2}\)
h= 500, A=2750

∑xi=200, \(\sum f_iu_i\)
(x̅) mean = A + \(\frac{\sum f_iu_i}{\sum f_i}\times h\)
(x̅) \(=2750+\frac{-35}{200}\times500\)
=2750-87.5
=2662.5
So, mean monthly expenditure was Rs. 2662.50