Question 208784
{{{(1-y)/(1+y)}}} = {{{2/3}}}
Cross multiply
3(1-y) = 2(1+y)
:
3 - 3y = 2 + 2y
:
3 - 2 = 2y + 3y
:
1 = 5y
y = {{{1/5}}}
:
:
Check solution using .2 for 1/5
{{{(1-.2)/(1+.2)}}} = {{{2/3}}}
{{{.8/1.2}}} = {{{2/3}}}