Question

Terri Vogel, an amateur motorcycle racer, averages 129.71 seconds per 2.5 mile lap (in a seven-lap race) with a standard deviation of 2.28 seconds. The distribution of her race times is normally distributed. We are interested in one of her randomly selected laps.

• Part (a)

  In words, define the random variable X.

  the time (in seconds) per lapthe time (in seconds) per race    the distance (in miles) of each racethe distance (in miles) of each lap

• Part (b)

  Give the distribution of X.
  X ~

• Part (c)

  Find the percent of her laps that are completed in less than 135 seconds. (Round your answer to two decimal places.)
  

• Part (d)

  The fastest 2% of her laps are under how many seconds? (Round your answer to two decimal places.)
  sec

• Part (e)

  Enter your answers to two decimal places.
  
  The middle 80% of her lap times are from  seconds to  seconds.

Answer 1