7.23+6.84+0.84+2.77簡便

7.23+6.84+0.84+2.77簡便


7.23+6.84+0.84+2.77
=(7.23+2.77)+6+(0.84+0.84)
=10+6+0.84*2
=16+1.68
=17.68



34.5*6.23-34.5+1.77*34.5
簡算


原式=34.5*(6.23-1+1.77)
=34.5*7
=241.5



計算0.23-七分之二+0.77-七分之五的最好方法是


原式=(0.23+0.77)-(2/7+5/7)
=1-1
=0



5又5分之5减(1.23—1又6分之1)—1.77=?
對不起應該是5又6分之5


5又5/5-(1.23-1又1/6)-1.77
=6-1.23+1又1/6-1.77
=7又1/6-(1.23+1.77)
=4又1/6