Question

28+320除4-30的简便算法

Answer 1

28+320÷4-30
=28+80-30
=28+(80-30)
=28+50
=78
或者是
(28+320)÷4-30
=28÷4+320÷4-30
=7+80-30
=7+（80-30）
=7+50
=57
你要哪个?