Calculus 1 : How to find constant of proportionality of rate

Study concepts, example questions & explanations for Calculus 1

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Example Questions

Example Question #121 : How To Find Constant Of Proportionality Of Rate

The rate of change of the number of yeast cells in a loaf of bread as it's put into the oven is proportional to the population. The population decreased by 99.7 percent between 5:00 and 6:00. What is the constant of proportionality in hours-1?

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value, and  is the constant of proportionality.

Since the population decreased by 99.7 percent between 5:00 and 6:00, we can solve for this constant of proportionality:

 

Example Question #122 : How To Find Constant Of Proportionality Of Rate

The rate of change of the number of cyborgs on Planet X-038 is proportional to the population. The population increased by 513 percent between 2039 and 2043. What is the constant of proportionality in years-1?

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value, and  is the constant of proportionality.

Since the population increased by 513 percent between 2039 and 2043, we can solve for this constant of proportionality:

Example Question #123 : How To Find Constant Of Proportionality Of Rate

The rate of change of the number of nanobots in an advancing horror of gray goo is proportional to the population. The population increased by 113800 percent between 2025 and 2028. What is the constant of proportionality in years-1?

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value, and  is the constant of proportionality.

Since the population increased by 113800 percent between 2025 and 2028, we can solve for this constant of proportionality:

Example Question #124 : How To Find Constant Of Proportionality Of Rate

The rate of change of the number of bacteriophages in a room where nobody covers their face after sneezing is proportional to the population. The population increased from 1,600 to 320,000 between 4:15 and 5:00. What is the constant of proportionality in minutes-1?

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value, and  is the constant of proportionality.

Since the population increased from 1,600 to 320,000 between 4:15 and 5:00, we can solve for this constant of proportionality:

Example Question #1021 : Rate

The rate of change of the number of leopard geckos is proportional to the population. The population increased by 45.5 percent between 2014 and 2015. What is the constant of proportionality in years-1?

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value, and  is the constant of proportionality.

Since the population increased by 45.5 percent between 2014 and 2015, we can solve for this constant of proportionality:

 

Example Question #1022 : Rate

The rate of decrease of the number of rupees due to plundering green-clad adventurers is proportional to the population. The population decreased from 999 to 25 between 3:30 and 5:42. What is the constant of proportionality in hours-1?

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value, and  is the constant of proportionality.

Since the population decreased from 999 to 25 between 3:30 and 5:42, we can solve for this constant of proportionality. Mind the units requested; divide the minutes by 60 to give decimals after the hour:

Example Question #1023 : Rate

The rate of loss of the number of jewelers' gold rings due to thieving hedgehogs is proportional to the population. The population decreased from 1000 to 50 between 3:30 and 3:45. What is the constant of proportionality in minutes-1?

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value, and  is the constant of proportionality.

Since the population decreased from 1000 to 50 between 3:30 and 3:45, we can solve for this constant of proportionality:

Example Question #1024 : Rate

The rate of change of the number of math problems is proportional to the population. The population increased from 10 to 2000 between 2014 and 2015. Determine the expected population in 2017.

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value,   represents a measure of elapsed time relative to this population value, and  is the constant of proportionality.

Since the population increased from 10 to 2000 between 2014 and 2015, we can solve for this constant of proportionality:

Now that the constant of proportionality is known, we can use it to find an expected population value relative to an initial population value due to the difference in time points:

Example Question #1021 : Rate

The rate of change of the number of bacteria on an old dish rag is proportional to the population. The population increased from 13 to 169 between 3:15 and 3:30. Determine the expected population at 4:00.

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value,   represents a measure of elapsed time relative to this population value, and  is the constant of proportionality.

Since the population increased from 13 to 169 between 3:15 and 3:30, we can solve for this constant of proportionality. Treating the minutes as decimals by dividing by 60:

Now that the constant of proportionality is known, we can use it to find an expected population value relative to an initial population value due to the difference in time points:

Example Question #1021 : Rate

The rate of change of the number of quiblobs due to the influence of morplibs is proportional to the population. The population increased from 18 to 324 between 2908 and 2909. Determine the expected population in 2921.

Possible Answers:

Correct answer:

Explanation:

We're told that the rate of change of the population is proportional to the population itself, meaning that this problem deals with exponential growth/decay. The population can be modeled thusly:

Where  is an initial population value,   represents a measure of elapsed time relative to this population value, and  is the constant of proportionality.

Since the population increased from 18 to 324 between 2908 and 2909, we can solve for this constant of proportionality:

Now that the constant of proportionality is known, we can use it to find an expected population value relative to an initial population value due to the difference in time points:

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