What is the percent of increase for a population that changed from 438,000 to 561,000

so the difference of 561,000 - 438,000 = 123000.

now, if we take 438,000, original amount, as the 100%, what is 123000 off of it in percentage?

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents