Which of the following is not a characteristic of the normal probability distribution?
a. symmetry
b. The total area under the curve is always equal to 1.
c. 99.72% of the time the random variable assumes a value within plus or minus 1 standard deviation of its mean
d. The mean is equal to the median, which is also equal to the mode.
Normal Distribution is symmetric distribution with mean = mode = medium.
Any Probability Distribution is distribution which have sum of probabilties of all the cases under distribution as 1.
Therefore options (a), (b) and (d) are correct.
plus or minus 1 standard deviation in normal distribution covers 68.3% and not 99.72%
Therefore answer is option (c)
Which of the following is not a characteristic of the normal probability distribution?