What was the percent increase in the population of city k from 1980 to 1990?

Do you have a picture but never the less I researched it and for this it says" in 1980 the population of City K was 20 percent greater than it was in 1970 and in 1990 the population of City K was 30 percent greater than it was in 1970"

He was paid 23 dollars for each lawn