The number of classes that are in the graph to the left are: 8 classes
The number of class intervals are: 5
How to Interpret the Histogram?
A histogram is a type of bar chart that represents the distribution of numerical data. It consists of bars that show the frequency or number of observations within different intervals, called bins. The height of each bar indicates the frequency of data points within the corresponding bin.
Now, the number of classes would be the number of blue bars that we see in the histogram.
In this case, the number of blue bars are: 8 classes
The reading on the y-axis shows the frequency of each class.
From the histogram, the width of each interval is the middle point of the bars given and as such, the middle point is:
(57.5 - 47.5)/2 = 5