In a histogram the area of each rectangle is proportional to
1)the class mark of the corresponding class interval
2)the class size of the corresponding class interval
3)frequency of the corresponding class interval
4)cumulative frequency of the corresponding class interval

Explanation

To solve the question regarding the area of rectangles in a histogram, we need to analyze the relationship between the area of each rectangle and the corresponding class interval.

### Step-by-Step Solution:

1. **Understanding Histogram Basics**:
- A histogram is a graphical representation of the distribution of numerical data. It consists of bars (rectangles) where the height of each bar represents the frequency of data within a particular range (class interval).

**Hint**: Remember that the height of each bar in a histogram corresponds to the frequency of the data in that interval.
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