What is a rule to find the sum of 1 plus 2 plus 3 plus 4 plus 5 plus 4 plus 3 plus 2 plus 1?

Answer 1

The answer is 25 but I do not know the rule. If someone else knows the rule feel free to edit my answer.

first thing i would like to tell that their no particular rule to solve this problem. But if we consider the working of calculator then the addition will be done as follows.

((((((((1+2)+3)+4)+5)+4)+3)+2)+1) = 25

(((((((3+3)+4)+5)+4)+3)+2)+1) = 25

((((((6+4)+5)+4)+3)+2)+1) = 25

(((((10+5)+4)+3)+2)+1) = 25

((((15+4)+3)+2)+1) = 25

(((19+3)+2)+1) = 25

((22+2)+1) = 25

(24+1) = 25

solve from innermost bracket towards outer

This is just a consideration of calculator if you solve through calculator the producer will look as above.

If any one knows any simple answer please feel free to continue this discussion.