Let ABCD be a parallelogram. Draw QN parallel to AB with Q lying on AD and N lying on BC. Draw another line MS parallel to AD with M lying on AB and S lying on QN. Draw yet another line PT parallel to AD with P lying on CD and T lying on QN.

The area of AMSQ, BNSM, CPTN and DQTP are respectively 12, 36, 48, and 24.
What is the area of quadrilateral BSDT?