document.write( "Question 1129899: A nurse needs 50 mL of a 16% salt solution for a patient. She can only find a 13% salt solution and an 18% salt solution in the supply room. How many millimeters of the 13% solution should be mixed with the 18% solution to produce the desired amount of the 16% solution? \n" ); document.write( "

Algebra.Com's Answer #746528 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+a+\"$ = mL of 13% solution needed
\n" ); document.write( "Let $\"+b+\"$ = mL of 18% solution needed
\n" ); document.write( "---------------------------------------------
\n" ); document.write( "(1) $\"+a+%2B+b+=+50+\"$
\n" ); document.write( "(2) $\"+%28+.13a+%2B+.18b+%29+%2F+50+=+.16+\"$
\n" ); document.write( "---------------------------------------
\n" ); document.write( "(2) $\"+.13a+%2B+.18b+=+8+\"$
\n" ); document.write( "(2) $\"+13a+%2B+18b+=+800+\"$
\n" ); document.write( "Multiply both sides of (1) by $\"+13+\"$ and
\n" ); document.write( "subtract (1) from (2)
\n" ); document.write( "(1) $\"+-13a+-+13b+=+-650+\"$
\n" ); document.write( "---------------------------------
\n" ); document.write( " $\"+5b+=+150+\"$
\n" ); document.write( " $\"+b+=+30+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+a+%2B+30+=+50+\"$
\n" ); document.write( "(1) $\"+a+=+20+\"$
\n" ); document.write( "You can finish \n" ); document.write( "

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