Question 0402d

Arithmetic and Geometric Progressions (APs, GPs)

GP IV

Question

A geometric series has positive first term

{a}

and common ratio

{0.9.}

Find the least value of

{n}

such that the sum of the first

{n}

terms of the series,

{S_n,}

is within

{23\%}

of the sum to infinity.

Least

{n = }