document.write( "Question 1190048: The mass of a substance, which follows a continuous exponential growth model, is being studied in a lab. The doubling time for this substance was observed to be 14 days. There were 9.3 mg of the substance present at the beginning of the study.
\n" ); document.write( "(a) Let t be the time (in days) since the beginning of the study, and let
\n" ); document.write( "y be the amount of the substance at time t.
\n" ); document.write( "Write a formula relating y to t.
\n" ); document.write( "Use exact expressions to fill in the missing parts of the formula.
\n" ); document.write( "Do not use approximations.\r
\n" ); document.write( "\n" ); document.write( "(b) How much will be present in 16 days?
\n" ); document.write( "Do not round any intermediate computations, and round your
\n" ); document.write( "answer to the nearest tenth \n" ); document.write( "

Algebra.Com's Answer #821607 by ikleyn(52790) $\"\"$ $\"About$

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\n" ); document.write( "The mass of a substance, which follows a continuous exponential growth model, is being studied in a lab.
\n" ); document.write( "The doubling time for this substance was observed to be 14 days.
\n" ); document.write( "There were 9.3 mg of the substance present at the beginning of the study.
\n" ); document.write( "(a) Let t be the time (in days) since the beginning of the study, and let
\n" ); document.write( "y be the amount of the substance at time t.
\n" ); document.write( "Write a formula relating y to t.
\n" ); document.write( "Use exact expressions to fill in the missing parts of the formula.
\n" ); document.write( "Do not use approximations.
\n" ); document.write( "(b) How much will be present in 16 days?
\n" ); document.write( "Do not round any intermediate computations, and round your
\n" ); document.write( "answer to the nearest tenth
\n" ); document.write( "~~~~~~~~~~~~~~~~~\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "

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document.write( "The formula is  \r\n" );
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document.write( "    y = 9.3*2^(t/14).\r\n" );
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document.write( "Notice that 9.3 is the initial amount at the beginning  (9.3 mg at t= 0).\r\n" );
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document.write( "The denominator \"14\" in the index of the exponential function is the doubling time of 14 minutes.\r\n" );
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document.write( "t is the current time in minutes.\r\n" );
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document.write( "To calculate the mass at t= 16 minutes,  substitute t= 16 into the formula and compute.\r\n" );
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\r
\n" ); document.write( "\n" ); document.write( "Solved and explained.\r
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\n" ); document.write( "\n" ); document.write( "To see many other solved problems on exponential growth/decay, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Population growth problems \r
\n" ); document.write( "\n" ); document.write( "    - Radioactive decay problems \r
\n" ); document.write( "\n" ); document.write( "    - Carbon dating problems \r
\n" ); document.write( "\n" ); document.write( "    - Bacteria growth problems \r
\n" ); document.write( "\n" ); document.write( "    - A medication decay in a human's body \r
\n" ); document.write( "\n" ); document.write( "    - Problems on appreciated/depreciated values \r
\n" ); document.write( "\n" ); document.write( "    - Inflation and Salary problems \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "        Consider these lessons as your handbook, textbook, guide, tutorials, and (free of charge) home teacher.\r
\n" ); document.write( "\n" ); document.write( "        Learn the subject from there once and for all.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Logarithms\".\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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