Third term = t3 = ar^2 = 444 eq. (1)
Seventh term = t7 = ar^6 = 7104 eq. (2)
By solving (1) and (2) we get,
 ar^2 = 444 
 => a = 444 / r^2 eq. (3)
And ar^6 = 7104
 (444/r^2)r^6 = 7104
 444 r^4 = 7104
 r^4 = 7104/444
 = 16
 r2 = 4
 r = 2
Substitute r value in (3) 
 a = 444 / r^2
 = 444 / 2^2
 = 444 / 4
 = 111
Therefore a = 111 and r = 2
Therefore t6 = ar^5
 = 111(2)^5
 = 111(32)
 = 3552.
Therefore the 6th term in the geometric series is 3552.