PP-T1-DS60

[max999]

What was the percent increase in the population of City K from 1980 to 1990 ?

(1) In 1970 the population of City K was 160,000
(2) 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.

answer:B

麻煩大大.thanks

[Huang Hsin-Yi]

(2)
120(1980)=100(1970)
130(1990)=100(1970)

問1990-1980/1980可由上面聯立解出來