Question 1132201
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<pre>
The condition explicitly says that


    154 = 0.55*X,


where X is the number of shirts sold (the week) <U>before increase</U>.


So,  X = {{{154/0.55}}} = 280.


Then the number of shirts sold for <U>this week of Xmas trading</U> is


    280*1.55 = 434.


<U>CHECK</U>.  {{{((434-280)/280)*100}}} = 55%.
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Solved.