Two numbers have a H.C.F of 20 and a product of two numbers is 2560. Find the L.C.M of the two numbers? Choose one:  A) 140  B) 150  C) 160  D) 128  E) 180

Rationale: l . c . m of two numbers is given by ( product of the two numbers ) / ( h . c . f of the two numbers ) = 2560 / 20 = 128 . answer : d
Answer: D