A pot of piping hot stew has been removed from the stove and left to cool.The relationship between the elapsed time, m, in minutes, since the stew was removed from the stove, and the temperature of the stew, T(m), measured in ∘C, is modeled by the following function.T(m)=20+50⋅10−0.04mHow many minutes will it take for the stew to cool to a temperature of 30∘C ?Round your answer, if necessary, to the nearest hundredth.□ minutes
Q. A pot of piping hot stew has been removed from the stove and left to cool.The relationship between the elapsed time, m, in minutes, since the stew was removed from the stove, and the temperature of the stew, T(m), measured in ∘C, is modeled by the following function.T(m)=20+50⋅10−0.04mHow many minutes will it take for the stew to cool to a temperature of 30∘C ?Round your answer, if necessary, to the nearest hundredth.□ minutes
Understand and Set up Equation: Understand the problem and set up the equation.We are given the temperature function T(m)=20+50×10(−0.04m), where T(m) is the temperature of the stew in degrees Celsius after m minutes. We need to find the value of m when T(m)=30°C.Set up the equation: 30=20+50×10(−0.04m).
Isolate Exponential Term: Isolate the exponential part of the equation.Subtract 20 from both sides of the equation to isolate the exponential term.30−20=50×10(−0.04m)10=50×10(−0.04m)
Divide to Solve Exponential Term: Divide both sides by 50 to solve for the exponential term.5010=10(−0.04m)0.2=10(−0.04m)
Take Logarithm to Solve for m: Take the logarithm of both sides to solve for m. Use the property of logarithms that log(ab)=b⋅log(a). log(0.2)=log(10−0.04m)log(0.2)=−0.04m⋅log(10) Since log(10) is 1, we can simplify this to: log(0.2)=−0.04m
Solve for m: Solve for m.Divide both sides by −0.04 to isolate m.m=−0.04log(0.2)Calculate the value of m using a calculator.m≈−0.04log(0.2)≈24.76
More problems from Interpret parts of quadratic expressions: word problems