In the diagram, the lines QR and ST are parallel to each other. The shortest distance
between these two lines is half the shortest distance between the point P and line
QR. What is the ratio of the area of the triangle PST to the area of the trapezium
SQRT?

Note: The figure shown is representative.

A.

13

B.

14

C.

25

D.

12

Solution:

There is a theorem

 12QR = ST  ΔPST  STQR =  12 [ST] h 12 h (ST + QR) )= ST ST + QR = ST  ST + 2ST = ST  3ST = 13