Question Number 160254 by rexford last updated on 26/Nov/21
Answered by qaz last updated on 26/Nov/21
$$\underset{\mathrm{i}=\mathrm{0}} {\overset{\infty} {\sum}}\mathrm{2}\left(\frac{\mathrm{4}}{\mathrm{5}^{\mathrm{i}} }\right)=\frac{\mathrm{8}}{\mathrm{1}−\frac{\mathrm{1}}{\mathrm{5}}}=\mathrm{10} \\ $$