Question 268809
{{{300000000*(1.075)^x=400000000}}}

{{{3(1.075)^x=4}}}

{{{1.075^x=4/3}}}

{{{x*log(1.075)=log(1.3333333)}}}

{{{x=(log(1.333333))/log(1.075)}}}


{{{x=0.1249386/0.031485}}}

{{{x=3.964}}}

About 4 years