document.write( "Question 695309: The time it takes for Jill to grade a set of tests depends on the amont of coffee that she drinks in the morning. After the customary 12 cups of coffee, a set of tests would only take 40 minutes to grade, on a slow morning though (when she only has 4 cups of cofee, a set of tests would take her one hour and twentytwo minutes. Write an equation expressing the grading time in terms of numbers of cups of coffee. \n" ); document.write( "
Algebra.Com's Answer #428420 by stanbon(75887)\"\" \"About 
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The time it takes for Jill to grade a set of tests depends on the amont of coffee that she drinks in the morning. After the customary 12 cups of coffee, a set of tests would only take 40 minutes to grade, on a slow morning though (when she only has 4 cups of cofee, a set of tests would take her one hour and twentytwo minutes. Write an equation expressing the grading time in terms of numbers of cups of coffee.
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\n" ); document.write( "You have 2 points relating time and cups: (12,40) and (4,82)
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\n" ); document.write( "slope = (82-40)/(4-12) = 42/-8 = -21/4
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\n" ); document.write( "Form: y = mx + b
\n" ); document.write( "Solve for \"b\":
\n" ); document.write( "82 = (-21/4)4 + b
\n" ); document.write( "b = 103
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\n" ); document.write( "Equation:
\n" ); document.write( "y = (-21/4)x + 103
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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