Choose the One Alternative That Best Completes the Statement or Answers

question 517

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
Solve the problem.
-Between 7:00 AM and 8:00 AM, trains arrive at a subway station at a rate of 15 trains per hour (0.25 trains per minute) . The following formula from statistics can be used to determine the probability that a train will arrive within t
Minutes of 7:00 AM. $$F ( t ) = 1 - e ^ { - 0.25 t }$$ Determine how many minutes are needed for the probability to reach 20%.

• A) \(0.89 \mathrm {~min}\)
• B) \(2.35 \mathrm {~min}\)
• C) \(5.34 \mathrm {~min}\)
• D) \(4.12 \mathrm {~min}\)