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In the following expression which number should be added so that it becomes a complete square?  1+3+7+9+11+13
Question

In the following expression which number should be added so that it becomes a complete square?
 1+3+7+9+11+13

A.

3

B.

5

C.

1

D.

7

Correct option is B

Given:
1+3+7+9+11+13
Concept Used :
The sum of consecutive odd numbers is a perfect square
Solution:
Current Sum
1+3+7+9+11+13 = 44
Check for the Nearest Perfect Square Greater than 44
To make 44 into a perfect square, we need to add a number to bring it to the nearest non-negative perfect square.
The nearest perfect square greater than 44 is 49 
Number to Add
To make the sum 49 , we need to add:
  = 49 - 44 = 5

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