\problemdata
{s01-ps7}
{basic counting}

\begin{problem}
\begin{enumerate}
\item There are 49 students in a class at MIT who either understand mathematical 
equations, exercise regularly, or love school. Of these:

\noindent
20 students understand mathematical equations.

\noindent
20 students exercise regularly.

\noindent
26 students love school.

\noindent
36 students understand mathematical equations or exercise regularly.

\noindent
38 students understand mathematical equations or love school.

\noindent
40 students exercise regularly or love school.

\vspace{1mm}

\noindent
How many students understand mathematical equations AND exercise
regularly AND love school?

\item Show that there are fewer than 
50,000 prime numbers less than or equal to 210,000. \hint they are actually far fewer than 50,000 (about 19,000)


\end{enumerate}
\end{problem}