### Theory:

Let us consider the data table given below and try to construct a histogram step-by-step.

Problem:

A private organization surveyed hundred schools in Chennai. The organization collected the average number of kindergarten children in each classroom.

The data table looks like this:

 Number of students $$25$$ - $$30$$ $$30$$ - $$35$$ $$35$$ - $$40$$ $$40$$ - $$45$$ $$45$$ - $$50$$ Frequency $$15$$ $$35$$ $$18$$ $$25$$ $$7$$

Now, let us try to construct a histogram.

Step $$1$$: Set and mark the units for $$X$$-axis and $$Y$$-axis.

Here, the axes will look like this:

Step $$2$$: Now mark the class intervals (Number of students) along the $$X$$-axis and the frequency along the $$Y$$-axis.

Step $$3$$: Now, construct rectangles with class intervals (number of students) as the base and the frequency as the height.