Compute

-

 1 + 3 + 5 + 7 + 9 + ……… 99 + 101


Calculator allowed. Only use for a number squared to use optimal method

Comments

  1. Rithvik25 February 2022 at 09:46

    First, we can start adding the first few up and see if we can spot a pattern.

    1 = 1
    1 + 3 = 4
    1 + 3 + 5 = 9
    1 + 3 + 5 + 7 = 16
    1 + 3 + 5 + 7 + 9 = 25

    Is there any pattern between 1, 4, 9, 16, 25?

    They are all square numbers.
    Now we have the pattern, we can carry on.

    The number of odd numbers in the original sum is 51. We find this out by adding up the first and last numbers, then dividing it by 2.

    This would now give us an answer of 51 squared

    ReplyDelete

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