In a school, it was decided that the no. of trees that each section of each class will plant, will be double of the class in which they r studying. If there are 1 to 12 classes in the school and each class has 2 sections, find how many trees were planted by the students.

please friends solve it n tell me the answer..! answer is 312 but i'm not sure about it..!!

hi poojan
it's a question from AP
Please inform the number of students in each section.
no. of students r nt required in this ques
Then, I think that the question is incomplete.


The Brainliest Answer!

This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Each section of each class will plant double the number of the class in which they are studying.

That means
each section of class 1 will plant= 1*2 = 2 trees, 
each section of class 2 will plant = 2*2 = 4 trees,
each section of class 3 will plant = 3*2 = 6 trees and so on.

Each class has 2 sections. 
So class 1 will plant 2*2 = 4 trees
class 2 will plant = 4*2 = 8 trees
class 3 will plant  = 6*2 = 12  trees and so on...

It is an AP with first term a=4, common difference, d = 8-4 = 4 and total 12 terms.

So total number of plants is

S_n =  \frac{n}{2}[2a+(n-1)d]\\ \\S_n=\frac{12}{2}[2 \times 4+(12-1) \times 4]\\ \\S_n=6[8+44]=6 \times52\\ \\S_n=312

Thus 312 trees were planted by students.
2 5 2
thanks alot dear..:)
you are welcome:)
:) :)