问题
解答题
计算下面各题. 2.7-0.8+1.3-0.19 3.5×0.8+6.5×80%
15
|
答案
(1)2.7-0.8+1.3-0.19,
=(2.7+1.3)-(0.8+0.19),
=4-0.99,
=3.01;
(2)3.5×0.8+6.5×80%,
=3.5×0.8+6.5×0.8,
=(3.5+6.5)×0.8,
=10×0.8,
=8;
(3)
÷[1-(2 15
+1 5
)],1 3
=
÷[1-2 15
],8 15
=
÷2 15
,7 15
=
;2 7
(4)15
+21 3
-55 11
,1 3
=15
-51 3
+21 3
,5 11
=10+2
,5 11
=12
.5 11