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The sum of all the two-digit odd numbers is

Options

  1. A2475
  2. B2530
  3. C4905
  4. D5049

Correct answer

A. 2475

Step-by-step solution

Sum of odd numbers = n ^2 Two-digit odd numbers are from 11-99 . Number of odd numbers from 1 to 99=50 Sum of odd numbers from 1 to 99=50^2=2500 Number of odd numbers from 1+9=5 Sum of odd numbers from 1 to 9=5^2=25 So, Sum of all two digit odd numbers =2500-25=2475 .

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