20題開頭求1的有理數加減。很容易犯錯誤。乘法也可以~ ~沒學除法就別打了~ ~至少記住20題。

② -4.2+5.7-8.4+10

③ (-40)-(+28)-(-19)+(-24)-(32)

④ -40-28-(-19)+(-24)-(-32)

⑤ 81.26-293.8+8.74+111

⑥ (+4.7)-(-8.9)-(+7.5)+(-6)

⑦ [1.8-(-1.2+2.1)-0.2]-(-1.5)

⑧ -216-157+348+512-678

⑨

⑩

⑾

⑿

⒀

⒁ (+3 )+(+4 )-(+1 )+(-3 )

⒂ 0.5+(- )-(-2.75)+

⒃(-15 )-[(-13 )+(-31 -14)]

⒄ (+3 )+(+4 )-(+1 )+(-3 )

⒅ -︱- -(- )︱-︱(- )+(- )︱

⒆ -︱-0.25︱+ -(-0.125)+ ︱-0.75︱