In a school students thought of planting trees in and around the schoo...
Let us assume that in a school there is only one section per class.
Then the Nos of trees planted per class are:
1,2,3,4,5,6,7,8,9,10,11,12
We see that the above is in AP with,
a=1 and d=1 l=12 n=12
we know,Sn=n/2(a+l)
S12=78
Thus considering that each class has a single section,total Nos of trees is 78.
However each class has 3 sections each.So Nos of trees planted=78*3
=234
In a school students thought of planting trees in and around the schoo...
Introduction:
In order to reduce air pollution, the students of a school have decided to plant trees in and around the school. They have come up with a plan where each section of each class will plant a certain number of trees based on the class they are studying in.
Explanation:
The plan is to have each section of a class plant the same number of trees as the class number. For example, the first section of class 1 will plant 1 tree, the second section of class 1 will plant 2 trees, and so on. This pattern will continue until class 12.
To calculate the total number of trees that will be planted by the students, we need to find the sum of the number of trees planted by each section in each class.
Calculating the number of trees:
Since there are three sections in each class, we need to calculate the sum for each section and then multiply it by 3 to get the total number of trees.
Section 1:
The number of trees planted by section 1 in each class can be calculated using the formula n(n+1)/2, where n is the class number. So, for class 1, section 1 will plant 1 tree, for class 2, section 1 will plant 3 trees, and so on.
Using the formula, we can calculate the sum of the number of trees planted by section 1 in each class:
1 + 3 + 6 + 10 + 15 + 21 + 28 + 36 + 45 + 55 + 66 + 78 = 352
Section 2:
Similarly, for section 2, we need to calculate the sum of the number of trees planted in each class using the formula.
Using the formula, we can calculate the sum of the number of trees planted by section 2 in each class:
2 + 4 + 7 + 11 + 16 + 22 + 29 + 37 + 46 + 56 + 67 + 79 = 403
Section 3:
Again, using the formula, we can calculate the sum of the number of trees planted by section 3 in each class:
3 + 5 + 8 + 12 + 17 + 23 + 30 + 38 + 47 + 57 + 68 + 80 = 454
Total number of trees:
To get the total number of trees planted by the students, we need to multiply the sum of each section by 3 since there are three sections in each class.
Total number of trees = (352 + 403 + 454) * 3 = 1209
Therefore, the students will plant a total of 1209 trees to reduce air pollution in and around the school.
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