Question 1054536
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The nth term is the sum of the first n terms of a G.P. 
with first term a<sub>1</sub> = 0.2 and common ratio r = 0.1:

0.2+0.02+0.002+0.0002+...+0.(n-1 zeros then a 2)

which, using the formula {{{S[n]=a[1](1-r^n)/(1-r)}}},

gives {{{0.2(1-0.1^n)/(1-0.1)}}} =

{{{0.2(1-0.1^n)/0.9}}} =

{{{expr(0.2/0.9)(1-0.1^n)}}} =

{{{expr(2/9)(1-0.1^n)}}} <--- formula for the nth term.

Edwin</pre></b></font>