Question 943507
Let {{{ n }}} = the number of divisions
{{{ ( 4/5 )*( 240/n ) = 240 / ( n + 4 ) }}}
{{{ 4*( 240/n ) = 5*240 / ( n + 4 ) }}} 
{{{ 960/n = 1200 / ( n + 4 ) }}}
{{{ 960*( n + 4 ) = 1200n }}}
{{{ 960n + 3840 = 1200n }}}
{{{ 240n = 3840 }}}
{{{ n = 16 }}}
There are 16 divisions
check:
{{{ ( 4/5 )*( 240/n ) = 240 / ( n + 4 ) }}}
{{{ ( 4/5 )*( 240/16 ) = 240 / 20 }}}
{{{ 960 / 80 = 120 / 10 }}}
{{{ 12 = 12 }}}
OK