问题
解答题
脱式计算(其中④、⑤两小题必须简算). ①730-240÷15×16 ②[2.06-(1.73-0.29)]×1.5 ③
④6.8+2.37+7.63+4.2 ⑤
|
答案
①730-240÷15×16,
=730-256,
=474;
②[2.06-(1.73-0.29)]×1.5,
=[2.06-1.44]×1.5,
=0.62×1.5,
=0.93;
③
÷[(7 12
+7 16
)×1 4
],8 33
=
÷[7 12
×11 16
],8 33
=
÷7 12
,1 6
=
×6,7 12
=
;7 2
④6.8+2.37+7.63+4.2,
=(6.8+4.2)+(2.37+7.63),
=11+10,
=21;
⑤
×17÷9+3÷8×5 8
,17 9
=
×17×5 8
+3×1 9
×1 8
,17 9
=
×5 8
+17 9
×3 8
,17 9
=(
+5 8
)×3 8
,17 9
=
.17 9