Question

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 example of section of class one will plant one tree section of class two wheel plant two trees and so on class 12 there are three sections of each class how many trees are planted by the students​

Answer 1

Answer:

Step-by-step explanation:

Given, there are 12 classes, with 3 sections each.

Also, the no. of trees planted is equal to the class in which the students are studying.

Therefore, the A.P will be:-

1st class- 1 x3 = 3trees

2nd class- 2 x 3 = 6trees

3rd class- 3x3 = 9 trees

..................................

12th class- 12 x 3 = 36trees

So, from the above data, we have that:

First term (a) = 3 ; last term (l) =36 ; n= 12 ; Sn=?

=>Sn = n/2 [a + l]

=>Sn = 12/2 [ 3 + 36 ]

= 6 ( 39 ) = 234 trees.

Thank you,

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