% increase in mean population from 1950 = 2,556,000,000 to
2000 = 6,279,000,000 =
ok it can sometimes be easier to put in an equation of sorts. 6,279,000,000=2,556,000,000 * x
then we multiply x by 100 to get %
making x the %increase
then just solve for x
so 6,279,000,000/2,556,000,000=x
x=2.4566
then multiply by 100
=245.66%
now this does sound like a lot but it is perfectly correct seeing that the population has more than doubled.
hope this helped