Normal Distribution


a normal distribution has a frequency curve which is bell-shaped.

many populations in real life have approximately normal distributions. e.g. heights, weights or iqs of a large group of people.

normal curves are symmetrical about the mean, median and mode.

solving problems involving normal distributions usually requires using the standard normal curve which has a mean of 0 and a standard deviation of 1.

the total area and probability under a standard normal curve is 1.

Key Skills

solve problems involving normal distributions


normal distributionnormal curve, standard normal curve, standard deviationmeanmedianmodez-scoresymmetry.