The number 2x10 to the 500, equates to 2.724 x10 to the 150... Is that correct and can you explain why?

Did you do the math? Many combinations of numbers can equal the same answer. For 100, you could have 1 X 100, 2X 50, 4X 25, 5X 20, 10X10

Please be clear with the question. We can't tell whether you mean this:

(2 x 10)^500 = (2.724 x 10)^150

or this:

2 x 10^500 = 2.724 x 10^150

or something else.