Answer :

Answer and workings in the attachment below.
View image Аноним
If you notice, the pattern is multiplication.

[tex]12*2 = 24, 24*3 = 72, 72* 4 = 288, 288* x = y[/tex]

Notice that it goes two-fold, then three-fold, then four-fold.  The next number would be 288*5, which is 1440.

Therefore, the next number is 1440.