问题
解答题
计算: (1)8+(-
(2)-22×7-(-3)×6+5; (3)-4.2-(-3
(4)70
(5)(-
(6)(-49)×(-0.125)+49×(-
|
答案
(1)原式=8+(-0.25)-5+0.25=(8-5)+(-0.25+0.25)=3;
(2)原式=-4×7+3×6+5=-28+18+5=-5;
(3)原式=[(-4.2)+(-5.8)]+(3
+53 7
)=-10+9=-1;4 7
(4)原式=(70+
)×(-15 16
)=-14-1 5
=-143 16
;3 16
(5)原式=(-
+7 9
-5 6
)×36-8÷9=-3 4
×36+7 9
×36-5 6
×36-3 4
=-28+30-27-8 9
=-258 9
;8 9
(6)原式=49×0.125-49×
+49×1 8
=49×[0.125-4 7
+1 8
]=49×4 7
=28.4 7