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**5 Characteristics, Concept, Uses and Importance of Normal Probability Curve**

The normal probability curve is the most widely used distribution. It is also known as “Gaussian Curve Probability”, named after the German mathematician Carl Friedrich Gauss who first discovered normal distribution. It displays the probability distribution for continuous random variable. The curve is of bell shaped and displays a concise image of the distribution. It is a continuous probability distribution that is symmetrical on both sides of the mean. It is the most important probability distribution in statistics as it shows the distribution of several naturally occurring variables.

Contents

**Characteristics of Normal Probability Curve **

The characteristics of a normal probability curve are:

i. The normal curve is symmetrical.

ii. The normal curve is bell-shaped.

iii. The mean, median and mode are equal.

iv. The Points of inflection occur at ± 1 Standard deviation unit.

v. It is asymptotic and unimodal as it has only one mode.

**Uses of Normal Probability Curve **

The uses of normal probability curve are as follows:

i. Determine the percentage of cases from the given scores.

ii. Determine the percentage of cases that are above or below the given score.

iii. Determine the limits of scores that include a given percentage of cases.

iv. To compare two distributions in terms of intersecting.

**Importance of ****Norm****al**** Probability Curve **

The following are the importance of normal probability curve:

i. It is useful in many natural phenomenon as it describes the distribution of values accurately.

ii. It shows the probability distribution for continuous random variable.

iii. In the field of statistics, it is considered the most vital probability distribution.

iv. It has numerous mathematical properties which makes it easy to manipulate.

v. Helpful in understanding distribution of factors in the population.