题目内容
脱式计算. 10.53÷(0.99-0.45+1.8) |
| ||||||||
3.75+4.5÷0.18×0.25 | 3000-144÷12×83. |
分析:(1)先算小括号里的减法,再算小括号里的加法,最后算括号外的除法,
(2)先算小括号里的加法,再算中括号里的乘法,最后算括号外的除法,
(3)先算除法,再算乘法,最后算加法,
(4)先算除法,再算乘法,最后算减法.
(2)先算小括号里的加法,再算中括号里的乘法,最后算括号外的除法,
(3)先算除法,再算乘法,最后算加法,
(4)先算除法,再算乘法,最后算减法.
解答:解:(1)10.53÷(0.99-0.45+1.8),
=10.53÷(0.54+1.8),
=10.53÷2.34,
=4.5;
(2)
÷[
×(
+
)],
=
÷[
×
],
=
÷
,
=6.25;
(3)3.75+4.5÷0.18×0.25,
=3.75+25×0.25,
=3.75+6.25,
=10;
(4)3000-144÷12×83,
=3000-12×83,
=3000-996,
=2004.
=10.53÷(0.54+1.8),
=10.53÷2.34,
=4.5;
(2)
1 |
8 |
1 |
25 |
2 |
5 |
1 |
10 |
=
1 |
8 |
1 |
25 |
1 |
2 |
=
1 |
8 |
1 |
50 |
=6.25;
(3)3.75+4.5÷0.18×0.25,
=3.75+25×0.25,
=3.75+6.25,
=10;
(4)3000-144÷12×83,
=3000-12×83,
=3000-996,
=2004.
点评:本题主要考查学生依据四则运算计算顺序进行计算,以及运用简便算法解决问题的能力.
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