Answer:
=6665
Step-by-step explanation:
The sum of a geometric series is given by:
Sn=a(1-rⁿ)/(1-r)
Sn is the sum of the first n terms, r is the rate and n is the number of terms.
r the quotient between any two consecutive numbers.
r=6/-1= -6
Sn=-1(1-(-6)⁶)/(1--6)
=46655/7
=6665
Sum of the first six terms=6665
