Question 1207330
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After pouring, the common height will be, obviously, the total volume divided by the total base area,
which is 25*30 + 25*18 = 1200 cm^2.


So, the answer is  {{{the_volume_of_the_liquid/total_base_area}}} = {{{(25*30*40)/1200}}} = {{{(25*1200)/1200}}} = 25 cm.
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Solved.