Question 1099900
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Half of 89 grams of "K" will remain after first 13 days,

and half of the half after next 13 days.


After all, it will be {{{(1/4)*89}}} grams of the substance "K" after 26 days.


<U>Answer</U>.  {{{(1/4)*89}}} = 22.25  grams of the substance "K" after 26 days.
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