If you have a discrete distribution, i.e. the values are integers, then the probability of 59 would be the equivalent of the group 58.5 to 59.5 in a continuous distribution.
58.5 corresponds to z1=((μ-58.5)/σ) and 59.5 to z2=((μ-59.5)/σ).
Assuming the distribution is normal, look up the z-tables to find the one-tail probabilities of z1 and z2. The difference between z1 and z2 will be the probability of getting between 58.5 and 59.5.
What is the probability of 59 if the mean is 60 and the standard deviation is 7?
3 answers
The average commute time via train from the Chicago O'Hare Airport to downtown is 60 minutes with a standard deviation of 15 minutes. Assume that the commute times are normally distributed. What proportion of commutes would be:
longer than 80 minutes?
less than 50 minutes?
between 45 and 75 minutes?
longer than 80 minutes?
less than 50 minutes?
between 45 and 75 minutes?
Quantitative Research - Tina, Saturday, May 28, 2011 at 7:52pm
The average commute time via train from the Chicago O'Hare Airport to downtown is 60 minutes with a standard deviation of 15 minutes. Assume that the commute times are normally distributed. What proportion of commutes would be:
longer than 80 minutes?
less than 50 minutes?
between 45 and 75 minutes?
The average commute time via train from the Chicago O'Hare Airport to downtown is 60 minutes with a standard deviation of 15 minutes. Assume that the commute times are normally distributed. What proportion of commutes would be:
longer than 80 minutes?
less than 50 minutes?
between 45 and 75 minutes?
0 answers