Find the sum of the first five terms of a geometric series with a1 = 0.28, a5 = 362.88 and r = 6

The sum of a geometric series is given by:

Sn=[a (r^n-1] / (r-1)

the nth term is given by

an=ar^ (n-1)

From the information given:

a1=0.28, r=6

the sum of the first 5 terms will be:

s₅=[0.28 (6^5-1) ] / (6-1)

s₅=[0.28 (7776-1) ]/5

s₅=2177/5

s₅=435.4