Answer
The horizontal asymptote of the graph is $\text{100 }\!\!%\!\!\text{ }$.
Work Step by Step
The degree of the numerator and denominator are equal, so the ratio of the numerator and denominator in $P\left( x \right)$ gives the horizontal asymptote.
The coefficients of x in the numerator and denominator in $P\left( x \right)$ are 100 and 1 respectively.
The horizontal asymptote of the graph of $P\left( x \right)$ is $\frac{100}{1}=100$.
The horizontal asymptote of the graph of $P\left( x \right)$ is 100.
This means the percentage of deaths due to smoking approach to 100 $%$ but never attain it.
