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In a school, students decided to plant 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 double of the class in which they are studying. If there are 1to 12 classes in the school and each class has two sections, find how many trees were

planted by the students. Which value is shown in this question?

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#### Solution

Solution:-

Class 1 plant trees = 2 x class 1 x 2 section = 2 x 1 x 2 = 4 x classs= 4 x 1 = 4 trees

Class 2 plant trees = 4 x classs = 4 x 2 = 8 trees a = 4

d = 8

n = 12

S12 = 12/2[2x4 + 11x4] = 312 trees

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