4225
You can use one of the formulae for the sum of an arithmetic progression to calculate that.
9 and 11
The sum of the first 100 odd numbers is 10,000.
The numbers are 43 and 45.
The sum of the first 60 consecutive odd numbers is 3,600.
The sum of the first 60 consecutive odd numbers is 3,600.
the sum of first 50 consecutive odd numbers is 9801
The sum of the first 600 consecutive odd numbers is 360,000.
The sum of the first 30 consecutive odd numbers is 900.
The sum of the first 350 consecutive odd numbers is 122,500.
The sum of the first 30 consecutive odd numbers is 900.
The sum of the first 900 consecutive odd numbers is 810,000.
The sum of the first 250 consecutive odd numbers is 250 squared or 62,500.
The sum of the first 450 consecutive odd numbers is 450 squared or 202,500.
The sum of the first 1,300 consecutive odd numbers is 1,300 squared or 1,690,000.
The sum of the first consecutive 800 odd numbers is 640,000.