
设原计划平均每天修路$x$千米,则实际每天修路$\left(1+\dfrac{1}{5}\right)x$千米,
由题意得,$\dfrac{36}{x}-\dfrac{36}{\left(1+\dfrac{1}{5}\right)x}=20$,
解得:$x=0.3$,
经检验:$x=0.3$是原分式方程的解,且符合题意.
$0.3$千米$=300$米.
答:原计划平均每天修路$300$米.

设原计划平均每天修路$x$千米,则实际每天修路$\left(1+\dfrac{1}{5}\right)x$千米,
由题意得,$\dfrac{36}{x}-\dfrac{36}{\left(1+\dfrac{1}{5}\right)x}=20$,
解得:$x=0.3$,
经检验:$x=0.3$是原分式方程的解,且符合题意.
$0.3$千米$=300$米.
答:原计划平均每天修路$300$米.