Question

Evaluate geometric series

Answer 1

7.5

Explanation:

Sum of a geometric series,

`\frac{a _(1)(1 - r {}^(n) ) }{1 - r}`

Where a1 is the first term, R is the common ratio, n is the number of terms.

a1 is 5

r is 1/3

n is 10.

`\frac{5(1 - ( (1)/(3) ){}^(10) ) }{ (2)/(3) }`

Which is about

7.50

Answer 2

Sn=a1(1-rn)1-r,r=1 is answer