Exponential Function Solution Equation - Decay (Discrete, Mis-matched Time Units) - Scenario to Time

Level 1

The topics in this unit focus on mastering exponential growth and decay functions. Work on practice problems directly here, or download the printable pdf worksheet to practice offline.

Exponential Function Solution Equation - Decay (Discrete, Mis-matched Time Units) - Scenario to Time Worksheet

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Exponential Function Solution Equation - Decay (Discrete, Mis-matched...
1
A toxin starts at a concentration of 800mg/L. Each daily dialysis reduces it by 3%. After a certain number of hours it has decreased to a concentration of 42mg/L.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 1 over 24 times \ln{\frac{42 over 800 }}{\ln{(1+0.03)}}
b A LaTex expression showing t = 24 times \ln{\frac{42 over 800 }}{\ln{(1-0.03)}}
c A LaTex expression showing t = 24 times \frac{\ln{42 times 800}}{\ln{(1-0.03)}}
2
A charitable endowment starts with $900. Each daily it disburses 5% of its remaining funds. After a certain number of years its funds have decreased to $771.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 1 over 365 times \ln{\frac{771 over 900 }}{\ln{(1-0.05)}}
b A LaTex expression showing t = 1 over 365 times \frac{\ln{771 times 900}}{\ln{(1-0.05)}}
c A LaTex expression showing t = 365 times \ln{\frac{771 over 900 }}{\ln{(1+0.05)}}
d A LaTex expression showing t = 365 times \ln{\frac{771 over 900 }}{\ln{(1-0.05)}}
3
A charitable endowment starts with $900. Each daily it disburses 2% of its remaining funds. After a certain number of years its funds have decreased to $830.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 365 times \ln{\frac{830 over 900 }}{\ln{(1+0.02)}}
b A LaTex expression showing t = 1 over 365 times \ln{\frac{830 over 900 }}{\ln{(1-0.02)}}
c A LaTex expression showing t = 365 times \ln{\frac{830 over 900 }}{\ln{(1-0.02)}}
4
A charitable endowment starts with $600. Each yearly it disburses 8% of its remaining funds. After a certain number of months its funds have decreased to $10.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 12 times \frac{\ln{10 times 600}}{\ln{(1-0.08)}}
b A LaTex expression showing t = 12 times \ln{\frac{10 over 600 }}{\ln{(1-0.08)}}
c A LaTex expression showing t = 1 over 12 times \ln{\frac{10 over 600 }}{\ln{(1+0.08)}}
5
A charitable endowment starts with $500. Each weekly it disburses 9% of its remaining funds. After a certain number of days its funds have decreased to $2.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 1 over 7 times \ln{\frac{2 over 500 }}{\ln{(1-0.09)}}
b A LaTex expression showing t = 7 times \ln{\frac{2 over 500 }}{\ln{(1-0.09)}}
c A LaTex expression showing t = 7 times \frac{\ln{2 times 500}}{\ln{(1-0.09)}}
6
A charitable endowment starts with $200. Each yearly it disburses 9% of its remaining funds. After a certain number of months its funds have decreased to $0.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 12 times \ln{\frac{0 over 200 }}{\ln{(1-0.09)}}
b A LaTex expression showing t = 1 over 12 times \ln{\frac{0 over 200 }}{\ln{(1+0.09)}}
c A LaTex expression showing t = 12 times \frac{\ln{0 times 200}}{\ln{(1-0.09)}}
d A LaTex expression showing t = 1 over 12 times \ln{\frac{0 over 200 }}{\ln{(1-0.09)}}
7
A charitable endowment starts with $900. Each yearly it disburses 4% of its remaining funds. After a certain number of months its funds have decreased to $17.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 1 over 12 times \ln{\frac{17 over 900 }}{\ln{(1-0.04)}}
b A LaTex expression showing t = 12 times \ln{\frac{17 over 900 }}{\ln{(1-0.04)}}
8
A toxin starts at a concentration of 200mg/L. Each daily dialysis reduces it by 7%. After a certain number of weeks it has decreased to a concentration of 149mg/L.
Rearrange the exponential equation to solve for for the time given this scenario?
a A LaTex expression showing t = 7 times \ln{\frac{149 over 200 }}{\ln{(1+0.07)}}
b A LaTex expression showing t = 1 over 7 times \frac{\ln{149 times 200}}{\ln{(1-0.07)}}
c A LaTex expression showing t = 1 over 7 times \ln{\frac{149 over 200 }}{\ln{(1-0.07)}}