50
575 is halfway between 550 and 600.
550 is halfway between 500 and 600
The halfway point between 500 and 600 is (500 + 600) ÷ 2 = 550
The year 550, as with any year between 501 and 600, fell in the sixth century.
550 to 600 is an increase not a decrease. Anyway, the amount of the increase is 9.09091%. If you go from 600 to 550 it is an 8.33% decrease.
How about: 550
550-600 years maybe
600
600
600
600
Any number between 300 and 600, such as 400, fits this criterion. Other examples include 350, 450, or 550. All these numbers are greater than 300 and less than 600.