在EXCEL中如F5要计算如D5小于30为0，大于30小于50乘以D5×6，大于50小于80乘以8,大于80乘以9，这如何写呀

=if(D5<30,0,if(D5<50,D5*6,if(D5<80,D5*8,D5*9)))

=IF(D5<30,0,IF(D5<50,D5*6,IF(D5<80,D5*8,IF(D5>80,D5*9))))
因为你没说30,50,80这些临界点,所以这几个数字没法判断,只要相应加上等号就行.

=LOOKUP(D5,{0,30,50,80;0,6,8,9})

=if(D5>80,D5*9,if(D5>50,D5,8,if(D5>30,D5*6,0)))

=IF(D5<30,0,IF(D5<50,D5*6,IF(D5<80,D5*8,D5*9)))