Question
As age increases, so does the likelihood of coronary heart disease (CHD). The percentage $P$ of people $x$ years old with signs of CHD is shown in the table.$$\begin{array}{rrrrrrrr}x & 15 & 25 & 35 & 45 & 55 & 65 & 75 \\ \hline P(\%) & 2 & 7 & 19 & 43 & 68 & 82 & 87\end{array}$$(a) Evaluate $P(25)$ and interpret the answer.(b) Find a function that models the data.(c) Graph $P$ and the data.(d) At what age does a person have a $50 \%$ chance of having signs of CHD?
Step 1
We see that when $x=25$, $P=7$. This means that 7% of people who are 25 years old have signs of coronary heart disease. So, $P(25)=7$. Show more…
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