In a school students thought of planting trees in and around the school to reduce air pollution. It was decided that the number of trees, that each section of each class will plant, will be the same as the class, in which they are studying, e.g., a section of Class I will plant 1 tree, a section of Class II will plant 2 trees and so on till Class XII. There are three sections of each class. How many trees will be planted by the students?

Explanation

To solve the problem of how many trees will be planted by the students, we can follow these steps:

### Step 1: Identify the number of trees planted by each class
Each class will plant a number of trees equal to their class number. For example:
- Class I (1st class) will plant 1 tree per section.
- Class II (2nd class) will plant 2 trees per section.
- Class III (3rd class) will plant 3 trees per section.
- This pattern continues up to Class XII (12th class), which will plant 12 trees per section.
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