The least perfect square, which is divisible by each of 21,36 and 66 is  Select the correct option:
A) 213444	B) 214344	C) 214434	D) 213443	E) none of these

Rationale: l . c . m . of 21 , 36 , 66 = 2772 . now , 2772 = 2 x 2 x 3 x 3 x 7 x 11 to make it a perfect square , it must be multiplied by 7 x 11 . so , required number = 22 x 32 x 72 x 112 = 213444 answer a
Answer: A