考點(diǎn):整數(shù)四則混合運(yùn)算,運(yùn)算定律與簡(jiǎn)便運(yùn)算,分?jǐn)?shù)的四則混合運(yùn)算
專題:運(yùn)算順序及法則,運(yùn)算定律及簡(jiǎn)算
分析:(1)先算除法,再算乘法,最后算減法;
(2)根據(jù)減法的性質(zhì)簡(jiǎn)算;
(3)先算乘除法,最后算加法;
(4)(5)先算括號(hào)里面的,再算括號(hào)外面的;
(6)根據(jù)乘法分配律簡(jiǎn)算.
解答:
解:(1)462-135÷15×26
=462-9×26
=462-234
=228
(2)6.38-(0.38+0.75)
=6.38-0.38-0.75
=6-0.75
=5.25
(3)
×
+
÷
=
+
=
(4)
÷[(
-
)×
]
=
÷[
×
]
=
÷
=
(5)
×(
÷
)
=
×
=
(6)12×(
+
-
)
=12×
+12×
-12×
=4+6-3
=7
點(diǎn)評(píng):計(jì)算四則混合運(yùn)算時(shí),要按照運(yùn)算順序,先算乘除,后算加減,有括號(hào)的先算括號(hào)里面的,再算括號(hào)外面的.能簡(jiǎn)算的要簡(jiǎn)算.