To calculate the value of "600 decreased by 20%", we can multiply 600 by 0.8:
600 × 0.8 = 480
To calculate "600 decreased by 20% and then increased by 20% of the result", we need to multiply 480 by 1.2:
480 × 1.2 = 576
Therefore, 600 decreased by 20% and then increased by 20% of the result is 576.
To find out which number is greater and by how much, we can subtract 576 from 600:
600 - 576 = 24
So, 600 is greater than 600 decreased by 20% and then increased by 20% of the result, by 24.