Question 1125757
term number 5,  {{{-2+(5-1)d=-2+4d}}}


term 7, {{{-2+6d}}}



Ratio of terms

{{{(-2+4d)/(-2+6d)=5/8}}}

{{{(2d-1)/(3d-1)=5/8}}}

{{{5(3d-1)=8(2d-1)}}}

{{{15d-5=16d-8}}}

{{{8-5=d}}}

{{{highlight(d=3)}}}