Question 906661
Let {{{ x }} = earnings for 1st week
{{{ 2x }}} = earnings for 2nd week
{{{ 4x }}} = earnings for 3rd week
{{{ 8x }}} = earnings for 4th week
--------------------------------
{{{ x + 2x + 4x + 8x = 15x }}}
{{{ 15x = 90 }}}
{{{ x = 6 }}}
She earned $6 the 1st week
--------------------------
check:
{{{ 6 + 12 + 24 + 48 = 90 }}}
{{{ 90 = 90 }}}
OK