Answer
By the year 2015.
Work Step by Step
Consider the provided condition. It shows that the average increase in the percentage is 2.4 each year and the initial percentage is 31%. So, for 67% the provided condition can be formulated as,
$31+2.4x=67$
Here, x shows the number of years after the year 2000.
Now, solve the above equation.
$\begin{align}
& 31+2.4x=67 \\
& 2.4x=67-31 \\
& x=\frac{36}{2.4} \\
& =15
\end{align}$
The above equation has x as the number of year after the year 2000. So the year in which the percentage will be 67% is,
$2000+15=2015$
Thus, 67% of all American adults will view a college education as essential for success by the year 2015.
