Solution:
$$\eqalign{
& {\text{Expenditure on steel}} \cr
& {\text{Year }}1991 = \frac{{{{50}^ \circ }}}{{{{360}^ \circ }}} \times 360000 \cr
& \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = {\text{Rs. }}50000 \cr
& {\text{Year }}2001 = \frac{{864000}}{{360}} \times 60 \cr
& \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = {\text{Rs. }}144000 \cr} $$
