比谁就是除以谁多的部分除以计划的：（700-500）/500*100%=40%
(700-500)/500=7/5-1=2/5=40%
700 - 500 = 200200 / 500 = 40%
(700-500)/500X100%=0.4x100%=40%
心算 40%
（700-500）÷500=40%
