Respuesta :

the fourth is 6, and the next one is 3. :)

Here the first term is a(1) = 48 and the common ratio (r) is 1/2.

Thus, a(n) = a(1)(1/2)^(n-1).  Check:  does this formula predict correctly that a(2)  = 24?      a(2) = 48(1/2) = 24.  YES.

a(3) = 12

a(4) = 48(1/2)^(4-1) = 48(1/2)^3 = 48/8 = 6

a(5) = 48(1/2)^5-1) = 48/16 = 3