document.write( "Question 1192880: A class of 30 students took two quizzes. Sixteen passed the first quiz and 20 passed the second. If 4 students failed both quizzes, how many passed both? \n" ); document.write( "

Algebra.Com's Answer #824797 by ikleyn(52790) $\"\"$ $\"About$

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\n" ); document.write( "A class of 30 students took two quizzes. Sixteen passed the first quiz and 20 passed the second.
\n" ); document.write( "If 4 students failed both quizzes, how many passed both?
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document.write( "From the condition, 30-16 = 14 failed the first quiz, and\r\n" );
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document.write( "                    30-20 = 10 failed the second quiz,\r\n" );
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document.write( "             while           4 failed both quizes.\r\n" );
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document.write( "Hence,  the number of those who failed at least one quiz is  14 + 10 - 4 = 20.\r\n" );
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document.write( "It means that 30-20 = 10 students passed both quizes.    ANSWER\r\n" );
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