**Question:**

A number "xy" is multiplied by another number "ab" and the result comes as "pqr" , where r=2y , q=2(x+y) and p=2x where x, y < 5 , q is not=0 , the value of ab may be : A.11 C.31 B.13 D.22

__2,2__

this can be written as

(10x+y) × ( 10a+b) = 100p +10q +r

substitute p,q,r

then we get

10x(10a+b-22) + y(10a +b -22)=0,,

since 10x+y cannot be zero

10a+b=22

ab =22