The second term of a geometric progress exceed the first term by 4 And the third term exceed the second term by 12 ,find the fourth term

ar - a = 4 ----> a(r-1) = 4 or a = 4/(r-1)

ar^2 - ar = 12 --> ar(r-1) = 12 or a = 12/(r(r-1))

4/(r-1) = 12/(r(r-1)
1 = 3/r
r = 3
in ar - a = 4
3a - a = 4
a = 2

term(4) = ar^3 = 2(27) = 54

check:
the terms are
2, 6, 18, 54

and 6-2 = 4 , check!
18-6 = 12, check!
my answer is correct