1 .

What value should come in place of question mark (?) in the following equations?$? \over 441$ = $16 \over ?$

[ A ]    72
[ B ]    84
[ C ]    96
[ D ]    108
[ E ]    124
 Answer : Option B Explanation : $(?)^ 2$ = 441 $\times$ 16 = $(21)^ 2$ $\times$ $(4)^2$ = $(21$\times$4)^ 2$ ? = 21 $\times$ 4 = 84