Q.

Assertion (A): ABCD is a trapezium with DC || AB. E and F are point on AD and BC respectively,  such that EF || AB. Then AEED=BFFC.

Reason (R): Any line parallel to parallel sides of a trapezium divides the non-parallel sides proportionally

1 Both A and R are true, and R is the correct explanation of A.  
2 Both A and R are true, but R is not the correct explanation of A.  
3 A is true, but R is false.  
4 A is false, but R is true  

Ans.

(1)

We joined AC which intersects EF at O.

As, EF  AB  EF  DC ( AB  DC)

In ΔADC, we have EO  DC

AEED=AOOC  (i)

Also, in ΔABC, we have AB  OF

AOOC=BFFC  (ii)                    From (i) and (ii), we get:

AEED=BFFC

Thus, Assertion (A) is true and Reason (R) is also true, and Reason (R) is the correct explanation of Assertion (A).   Therefore, option (a) is correct.