Solution:

The hare and the tortoise are together covering the distance at 9 miles per hour (i.e., on adding their speeds).
So, they will cover the distance of 81 miles in 9 hours.
Thus, in 9 hours, they will meet and the hare will have traveled 63 miles.

Alternative Solution through Equations:

Note that : Distance = Speed × Time

Let t be the time before the hare and the tortoise meet.
In t hours, the hare will travel 7 t miles.
In t hours, the tortoise will travel 2 t miles.

Now,
7 t + 2 t = 81
So, t = 81 ⁄ 9 = 9 hours.

Thus, distance traveled by hare before meeting = 7 × 9 = 63 miles.

Food for thought:

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