prep-ds-60

Kath1985

60.5054-!-item-!-187;#058&004422

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.

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【答案】B
請問(2)要百分比算出來是多少呢 ? PP解釋看過了 還是不懂...  
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