Exponential Equations & Modelling

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turkey-yks 2012 Q31 Evaluate Expression Given Exponential/Logarithmic Conditions
$$\begin{aligned} & 2 ^ { x } = \frac { 1 } { 5 } \\ & 3 ^ { y } = \frac { 1 } { 4 } \end{aligned}$$
Given this, what is the value of the product $x \cdot y$?
A) $\frac { \ln 3 } { \ln 2 }$
B) $\frac { \ln 15 } { \ln 2 }$
C) $\frac { \ln 5 } { \ln 4 }$
D) $\frac { \ln 25 } { \ln 3 }$
E) $\frac { \ln 5 } { \ln 6 }$
turkey-yks 2013 Q4 Solve Exponential Equation for Unknown Variable
$$4 ^ { x } \cdot 6 ^ { x } \cdot 9 ^ { x } = 36$$
Given this, what is x?
A) $\frac { 2 } { 3 }$
B) $\frac { 1 } { 4 }$
C) $\frac { 3 } { 4 }$
D) $\frac { 3 } { 8 }$
E) $\frac { 4 } { 9 }$
turkey-yks 2013 Q29 Solve Exponential Equation for Unknown Variable
$$\log _ { 8 } \left( \log _ { 9 } ( \sqrt { x + 1 } ) \right) = \frac { - 2 } { 3 }$$
Given this, what is x?
A) 2
B) 3
C) 5
D) 7
E) 8
turkey-yks 2013 Q31 Solve Exponential Equation for Unknown Variable
$$9 ^ { x + 1 } + 3 ^ { x + 1 } - 6 = 0$$
Given this, which of the following is x?
A) $\frac { \ln 3 } { \ln 2 }$
B) $\frac { 1 + \ln 3 } { \ln 2 }$
C) $\frac { 2 + \ln 3 } { \ln 2 }$
D) $\frac { 3 + \ln 2 } { \ln 3 }$
E) $\frac { \ln 2 - \ln 3 } { \ln 3 }$
turkey-yks 2014 Q3 Evaluate Expression Given Exponential/Logarithmic Conditions
$$4 ^ { x - 2 } = 6 ^ { 2 x - 2 }$$
Given that, what is the value of the expression $9 ^ { \mathbf { x } }$?
A) $\frac { 9 } { 2 }$
B) $\frac { 4 } { 3 }$
C) $\frac { 8 } { 3 }$
D) $\frac { 5 } { 4 }$
E) $\frac { 9 } { 4 }$
turkey-yks 2016 Q10 Solve Exponential Equation for Unknown Variable
$$3 ^ { x } \cdot 12 ^ { 2 - x } = 18$$
Given this, what is $x$?
A) $\frac { 1 } { 2 }$
B) $\frac { 3 } { 2 }$
C) $\frac { 1 } { 3 }$
D) $\frac { 4 } { 3 }$
E) $\frac { 5 } { 4 }$
turkey-yks 2017 Q32 Solve Exponential Equation for Unknown Variable
$x ^ { \ln 4 } - 6 \cdot 2 ^ { \ln x } + 8 = 0$\ What is the product of the $x$ values that satisfy this equation?\ A) $e ^ { 6 }$\ B) $e ^ { 4 }$\ C) $e ^ { 3 }$\ D) $\frac { e ^ { 2 } } { 2 }$\ E) $\frac { e ^ { 3 } } { 3 }$
turkey-yks 2021 Q25 Percentage Change and Growth Rate Reasoning
Temperature conversions between Fahrenheit (${}^{\circ}\mathrm{F}$) and Celsius (${}^{\circ}\mathrm{C}$) are calculated using the formula $\mathrm{F} = \frac{9}{5} \cdot \mathrm{C} + 32$.
Cem has been assigned to measure the classroom temperature in Celsius at the same time each day for five days they go to school and find the average temperature of these five days in Celsius. On one of these five days, Cem did not go to school, and his classmate Deniz took the measurement for that day. However, Deniz mistakenly recorded the F value instead of the C value for that day's temperature in the list. Based on the values in the list, Cem calculated the average temperature for these five days as $33.8^{\circ}\mathrm{C}$.
\cline{2-6} \multicolumn{1}{c|}{}MondayTuesdayWednesdayThursdayFriday
Temperature (${}^{\circ}\mathrm{C}$)2327252026

After Deniz's measured temperature value is converted to Celsius and the five-day measurement has the values in the list as shown above, on which day did Cem not go to school?
A) Monday B) Tuesday C) Wednesday D) Thursday E) Friday