For this case we have:
[tex]2 \frac {1} {6} = 2 + \frac {1} {6} = \frac {6 * 2 + 1 * 1} {6 * 1} = \frac {13} {6}[/tex]
This number represents the wide of the piece of land.
Also, if they tell us that the piece of land is 3 times longer than it is wide, then:
[tex]Long = \frac {wide} {3} = \frac {\frac {13} {6}} {3} = \frac {13 * 1} {3 * 6} = \frac {13} {18}[/tex]
Thus, the long of the piece of land is [tex]\frac {13} {18}[/tex] miles
ANswer:
[tex]\frac {13} {18}[/tex] miles