In: Statistics and Probability
The average time spent sleeping per night for a group of medical residents is 6.1 hours with a standard deviation of 1.0 hour. Between what two values do the middle 50% of the sleep times fall?
According to the z score table middle 50% of the values lie between 0.2483 and 0.7486, and their respective z scores are - 0.68 and 0.67
1st value,
X - 6.1/1 = - 0.68
X - 6.1 = - 0.68
X = 5.42
2nd value,
X - 6.1/1 = 0.67
X - 6.1 = 0.67
X = 6.77
So, between (5.42 and 6.77) 50% of the sleep time falls