Explain why a frequency distribution graph is normally a bell shaped curve but may be skewed?

A frequency distribution graph is normally a bell-shaped curve because it represents a normal distribution of data, where the majority of the data points cluster around the mean and taper off towards the extremes. This creates a symmetrical shape with a peak at the mean.

However, a frequency distribution graph may be skewed if the data is not normally distributed. Skewness occurs when the data is not evenly distributed around the mean, causing the graph to be asymmetrical. There are two types of skewness: positive skewness, where the tail of the graph extends to the right of the peak, and negative skewness, where the tail extends to the left.

Skewness can be caused by outliers, errors in data collection, or natural variations in the data. When a frequency distribution graph is skewed, it indicates that the data is not evenly distributed and may require further analysis to understand the underlying factors influencing the distribution.