The number of electric vehicles () sold in the United States within 3 years of their introduction to the market can be modeled by the logarithmic function , where is the number of vehicles sold in thousands and is the number of years after introduction to the market. The number of hybrid vehicles () sold within 3 years of their introduction to the market can be modeled by the logarithmic function . At what value of was an equal number of each vehicle sold, and which type of vehicle had greater sales over the 3 introductory years? Explain your reasoning with references to the terms in the function and how they compare.

Set .

Solve the resulting equation for .

Rewrite the resulting equation using an inverse function.

Interpret the resulting value of in terms of the conditions of the original problem.

Check the value of found in step 3 by substituting it back into the functions and .

Show which vehicle type had greater sales over the 3-year period by comparing the characteristics of each function.

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