總產出 (Total output)的計算 - 經濟

3. The fundamental equation of economic growth says that: Total output =
a. Productivity x Population
b. Productivity x Average Hours x Employment-Population Ratio
c. Productivity x Average Hours x Employment-Population Ratio x Population
d. Productivity x Average Hours x Population
e. Average Hours x Employment x Employment-Population Ratio

ANS: C

想請問大家這題為什麼是C.

總產出=生產力x平均工時x就業人口比(ERP)x總人口數

但是我不懂方程式後面的最後一項

Productivity x Average Hours x Employment-Population Ratio x Population
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~??

請大家幫幫忙!!
謝謝!!


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