-1/60÷(1/3+1/4+1/5)

问题描述:

-1/60÷(1/3+1/4+1/5)

-1/60÷(1/3+1/4+1/5)
=-1/60÷(20/60+15/60+12/60)
=-1/60÷47/60
=-1/47