$HCF \times LCM$ =Product of numbers
$a \times 18=36 \times 2$
$a=\large\frac{36 \times 2}{18}$
$\quad= 4$
$\large\frac{AB}{BC} =\frac{5}{12}$
$\qquad= \large\frac{h}{x+192}$
$\qquad= 5x+960$
$\qquad= 12\;h$
$\large\frac{AB}{PBD} =\frac{h}{x}$
$\qquad= \large\frac{3}{4}$
$4h=3x$
$5x+960=9x$
$x= 240\;m$
Answer :240 m