Question 1073700
The price won't affect the answer,
so, I'll say the dress costs $125
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Then it gets marked down by 20%, so
the discounted price is:
{{{ 125 - .2*125 = 125 - 25 }}}
{{{ 125 - 25 = 100 }}}
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Then the price goes back to $125
From the discounted price, the dress 
got increased by
{{{ ( 125 - 100 ) / 100 = 25/100 }}}
{{{ ( 25/100 )*100 = 25 }}}
25%