Determine the 4th term in the geometric sequence whose first term is - 2 and whose common ratio is - 5

Again, any geometric sequence can be expressed as:

a (n) = ar^ (n-1), a=initial term, r=common ratio, n=term number

We are told that a=-2 and r=-5 so:

a (4) = - 2 (-5) ^ (4-1)

a (4) = - 2 (-5) ^3

a (4) = 250