Question 1143033
Let {{{ C }}} = cost before discount
{{{ 100 = ( 1 - .2 )*C }}}
{{{ 100 = .8C }}}
{{{ C = 125 }}}
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(a)
{{{ 125 - 100 = 25 }}}
25 is the savings
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(b)
{{{ 25/4 = 6.25 }}}
6.25 is the average savings