document.write( "Question 1134892: On the colorimetric analysis to detect the presence of nitrates
\n" ); document.write( "in the water of the lakes, we know that if a sample contains nitrate
\n" ); document.write( "When pouring a certain solution into the water, it turns red on
\n" ); document.write( "95% of the time When you pour that solution into samples of
\n" ); document.write( "water that does not contain nitrates, the water turns red 10% of the
\n" ); document.write( "times (as a consequence of the presence of other chemicals that are
\n" ); document.write( "present and also react with the agent). Past experience
\n" ); document.write( "in a laboratory indicates that 30% of the water samples that are sent
\n" ); document.write( "to analyze contain nitrates.
\n" ); document.write( "a) If a sample of water samples sent to the laboratory is chosen, a
\n" ); document.write( "randomly, what is the probability that it will turn red
\n" ); document.write( "when analyzed?
\n" ); document.write( "b) If a water sample is chosen randomly and turns red
\n" ); document.write( "when analyzing, what is the probability that actually
\n" ); document.write( "contain nitrates? \n" ); document.write( "

Algebra.Com's Answer #752392 by Glaviolette(140) $\"\"$ $\"About$

You can put this solution on YOUR website!
I set up a tree diagram and then calculated the probabilities.
\n" ); document.write( "

\n" ); document.write( "

\n" );