document.write( "Question 426394: when 25 students went to Washington DC 18 of them visited the Museum of National History and 22 visited the natioonal air and space museum. how many students visited both? \n" ); document.write( "
Algebra.Com's Answer #296609 by edjones(8007)\"\" \"About 
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Asuming that each student went to at least one of the museums then 15 saw both.
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