Question

某工程队要修路m米,原计划平均可修n米,实际平均每天多p修了米,结果提前完成了任务,问提前了多少天?

Answer 1

m/n-m/(n+p)

=[m(n+p)]/[n(n+p)]-(mn)/[n(n+p)]

=(mn+mp)/(n^2+np)-(mn)/(n^2+np)

=(mp)/(n^2+np)天