Answer:
100.9 yards
Step-by-step explanation:
One circuit of the track is a distance of ...
C = 2πr = 2π(60 yd) = 120π yd.
At Alex's running rate, the distance covered in 20 minutes is ...
(4 yd/s)(20 min)(60 s/min) = 4800 yd
The number of circuits will be ...
(4800 yd)/(120π yd/circuit) = 40/π circuits ≈ 12.7324 circuits
The last of Alex's laps is more than half-completed, so the shortest distance to his starting point is 13 -12.7324 = 0.2676 circuits,
That distance is (0.2676 circuits)×(120π yd/circuit) ≈ 100.88 yd
The shortest distance along the track to Alex's starting point is about 100.9 yards.
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<em>Additional comment</em>
The exact distance is 120(13π-40) yards. The distance will vary according to your approximation for pi. If you use 3.14, this is about 98.4 yards.
