The complete question says:
"Wendy's restaurant has been recognized for having the fastest average service time among fast food restaurants. In a benchmark study, Wendy's average service time of 2.2 minutes was less than those of Burger King, Chick-fil-A, Krystal, McDonald's, Taco Bell, and Taco John's (QSR Magazine website, December 2014). Assume that the service time for Wendy's has an exponential distribution.
"Wendy's restaurant has been recognized for having the fastest average service time among fast food restaurants. In a benchmark study, Wendy's average service time of 2.2 minutes was less than those of Burger King, Chick-fil-A, Krystal, McDonald's, Taco Bell, and Taco John's (QSR Magazine website, December 2014). Assume that the service time for Wendy's has an exponential distribution.
a. What is the probability that a service time is less than or equal to one minute (to 4 decimals)?"
The exponential distribution probability is given by the formula:
where:
λ = average in unit time = 1/2.2 = 0.45 services per minute
t = time requested = 1 minute
p(T ≤ 1) = 0.3624
Hence, <span>the probability that a service time is less than or equal to one minute is p = 0.3624, which means 36.24%.</span>