Question

No copy and paste answers.

Answer 1

Answer:

  2.5 miles

Step-by-step explanation:

The relation between time, speed, and distance is ...

  distance = speed × time

We can define t to be Stanley's swimming time. Then t+0.5 was his running time, and 2(t+0.5) was his biking time. His total distance covered is ...

  64 = 9(t +0.5) +16(2(t +0.5)) +2.5(t)

  64 = 43.5t +20.5 . . . . . . . simplify

  43.5 = 43.5t . . . . . . . . . subtract 20.5

  t = 1 . . . . . . . . . . . . . . divide by the coefficient of t

Stanley swam for 1 hour, so the distance he covered while swimming was ...

  (2.5 mi/h)(1 h) = 2.5 mi

Stanley covered 2.5 miles while swimming.

_____

Additional comment

Stanley ran for 1.5 hours, covering 9×1.5 = 13.5 miles. He biked for 3 hours, covering 16×3 = 48 miles. His total distance was 2.5 +13.5 +48 = 64 miles, as given.