Square Roots And Cube Roots Q18

18.      The least perfect square, which is divisible by each of 21, 36 and 66 is:

     A.   213444

     B.   214344

     C.   214434

     D.   231444

Answer:

Option : A 

L.C.M.of21,36,66=2772.

Now,2772=2x2x3x3x7x11

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