Question 490152
The number of cubic feet of sand left in the pile after "X" scoops is:
a)
{{{ 50 - (1/6)*x }}} ft3
b)
{{{ 50 - (1/6)*12 = 48 }}} ft3
c)
20 ft3 remained 
{{{ 20 = 50 - (1/6)*x }}}
Subtract {{{ 50 }}} from both sides
{{{ -30 = -(1/6)*x }}}
Multiply both sides by {{{-1}}}
{{{ (1/6)*x = 30 }}}
{{{ x = 180 }}}
She shoveled 180 scoops before resting