1.5*80%=4
2.(100-5)/100 *100%=95%
3.( 80-50)/50 *100%=60%
(80-50)/80 *100%=37.5%
4个红球过程:设红球X个.X除以5=0.8 X=4
(100-5)除以100=95%
(80-50)除以50=0.6
(80-50)除以80=0.375
5×0.8=4(红球的个数是4个)
(100-5)÷100×100%=95%
(1)(80-50)÷50×100%=60%(比什么多就除以什么)
(2)(80-50)÷80×100%=37.5%
1、1.5×80%
2、5/(5+100)
3、(1)(80-50)/50
(2)(80-50)/80