Without adding, find the sum of the following:
$1+3+5+7+9+11+13$
Given :
The given expression is $1+3+5+7+9+11+13$
To do :
We have to find the sum without adding.
Solution :
We know that,
The Sum of 'n' consecutive odd numbers is $n^2$.
In the given sum there are 7 consecutive odd numbers.
Therefore,
$n = 7$
$n^2 = 7^2 =49$.
$1+3+5+7+9+11+13 = 49$.
Therefore, the sum of the given expression is 49.
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