A mug of warm apple cider is gradually cooling. Its temperature in degrees Celsius (∘C) can be modeled with the expression 23+24⋅2−0.014t, where the variable t represents the time in minutes. Approximately how many minutes will it take for the temperature to reach 29∘C? (Round to the nearest minute.)
Q. A mug of warm apple cider is gradually cooling. Its temperature in degrees Celsius (∘C) can be modeled with the expression 23+24⋅2−0.014t, where the variable t represents the time in minutes. Approximately how many minutes will it take for the temperature to reach 29∘C? (Round to the nearest minute.)
Write Equation: Write down the given temperature model equation.We have the temperature model equation: T(t)=23+24×2−0.014t, where T(t) is the temperature in degrees Celsius at time t minutes.
Set Equal to 29: Set the temperature model equation equal to 29 degrees Celsius to find the time t when the temperature will be 29 degrees Celsius.29=23+24×2(−0.014t)
Subtract and Isolate: Subtract 23 from both sides of the equation to isolate the exponential term.29−23=24×2(−0.014t)6=24×2(−0.014t)
Divide and Solve: Divide both sides of the equation by 24 to solve for the exponential term.246=2(−0.014t)41=2(−0.014t)
Take Logarithm: Take the logarithm of both sides of the equation to solve for t. We will use the natural logarithm (ln) and the property that ln(ab)=b⋅ln(a).ln(41)=ln(2−0.014t)ln(41)=−0.014t⋅ln(2)
Divide and Calculate: Divide both sides of the equation by −0.014×ln(2) to solve for t.t=−0.014×ln(2)ln(41)
Calculate t: Calculate the value of t using a calculator.t≈(−0.014×ln(2))ln(0.25)t≈(−0.014×0.69314718056)−1.38629436112t≈(−0.00970303639488)−1.38629436112t≈142.857142857
Round to Nearest Minute: Round the value of t to the nearest minute.t≈143 minutes
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