Question

ABCD is a parallelogram and point P bisects the base AB. Prove that ar(CPB)= 1/4 ar(ABCD)

Answer 1

CP is the median of the triangle ABC.
So,
Area of triangle CPB  = 1/2 area of triangle CAB = 1/2 × 1/2 area of ║ABCD = 1/4 area of ║ ABCD
 [Since diagonal divides the paralellogram into 2 equal triangles. ]
 
i have attached a figure also with it