(A) 252
(B) 238
(C) 630
(D) 945
Correct Option is: D
If three kinds of pets are taken be 3k,7k and 5k respectively, then 7k−3k=63p (where pp is any positive
integer).
As the number is a multiple of both 9 and 7, it has to be multiple of 63.
k = 63p/4
Minimum value of pp for which kk is a natural number is 4
Thus, k =63
Hence, the number of pets =15k= 945