Question 189944
we have the equation as:

{{{ (3/5)/b = 8/5 }}}

we know that b can also be written as b over 1, that is b/1.

so the equation becomes;

{{{ (3/5)/(b/1) = 8/5 }}}

we also know the concept of reciprocals that:
{{{ (a/b)/(c/d) = (a/b) * (d/c) }}}

so we first we reduce our equation as:

{{{ 3/5 * 1/b = 8/5 }}}

or, {{{ 3/(5*b) = 8/5 }}}
now cross multiply, we get:

{{{ 3*5 = (5*b) * 8 }}}
=> {{{ 15 = 40*b }}}
=> {{{ b = 15/40 }}}
=> {{{ b = 3/8 }}} (in the lowest fraction terms)

so, that's our answer.
Hope this helps you.