The mean time to get an oil change done at Leakys Garage is
     The mean time to get an oil change done at Leaky\'s Garage is 49 minutes, with a standard deviation of 11 minutes. Assuming a normal distribution, what is the probability that a randomly chosen customer experiences an oil change done between 49 and 71 minutes?  0.6826  0.5000  0.4772  0.3413 
  
  Solution
Mean=49
Standard deviation=11
For 49 minute, z=(49-49)/11=0
For 71 minute, z=(71-49)/11=22/11=2
By probality Table P(0<z<2)=0.4772 ans

