Question 860264
Let {{{ t }}} = the total bill
{{{ t/10 }}} = what each one would have paid with 10 people
{{{ t/9 }}} = what each one paid after one left
---------------------
{{{ t/9 - t/10 = .6 }}}
{{{ t/9 - t/10 = 6/10 }}}
Multiply both sides by {{{ 90 }}}
{{{ 10t - 9t - 54 }}}
{{{ t = 54 }}}
The bill was $54
---------------
check:
{{{ t/9 - t/10 = .6 }}}
{{{ 54/9 - 54/10 = .6 }}}
{{{ 6 - 5.4 = .6 }}}
{{{ .6 = .6 }}}
OK