题目内容
怎样算简便就怎样算.
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①
+
+
,
=[18×(
+
+
)]÷18,
=[18×
+18×
+18×
]÷18,
=[6+3+4]÷18,
=
;
②
+
-
,
=[28×(
+
-
)]÷28,
=[28×
+28×
-28×
]÷28,
=[12+21-22]÷28,
=11÷28,
=
;
③
-(
+
),
=
-
-
,
=0;
④
-
-
,
=
-(
+
),
=
-1,
=
;
⑤
+
+
-
,
=(
+
)+(
-
),
=1+
,
=1
;
⑥
-
+
-
,
=(
+
)-(
+
),
=1-
,
=
.
| 1 |
| 3 |
| 1 |
| 6 |
| 2 |
| 9 |
=[18×(
| 1 |
| 3 |
| 1 |
| 6 |
| 2 |
| 9 |
=[18×
| 1 |
| 3 |
| 1 |
| 6 |
| 2 |
| 9 |
=[6+3+4]÷18,
=
| 13 |
| 18 |
②
| 3 |
| 7 |
| 3 |
| 4 |
| 11 |
| 14 |
=[28×(
| 3 |
| 7 |
| 3 |
| 4 |
| 11 |
| 14 |
=[28×
| 3 |
| 7 |
| 3 |
| 4 |
| 11 |
| 14 |
=[12+21-22]÷28,
=11÷28,
=
| 11 |
| 28 |
③
| 5 |
| 8 |
| 3 |
| 8 |
| 1 |
| 4 |
=
| 5 |
| 8 |
| 3 |
| 8 |
| 2 |
| 8 |
=0;
④
| 8 |
| 7 |
| 5 |
| 9 |
| 4 |
| 9 |
=
| 8 |
| 7 |
| 5 |
| 9 |
| 4 |
| 9 |
=
| 8 |
| 7 |
=
| 1 |
| 7 |
⑤
| 4 |
| 15 |
| 7 |
| 9 |
| 11 |
| 15 |
| 4 |
| 9 |
=(
| 4 |
| 15 |
| 11 |
| 15 |
| 7 |
| 9 |
| 4 |
| 9 |
=1+
| 1 |
| 3 |
=1
| 1 |
| 3 |
⑥
| 9 |
| 14 |
| 3 |
| 8 |
| 5 |
| 14 |
| 1 |
| 8 |
=(
| 9 |
| 14 |
| 5 |
| 14 |
| 3 |
| 8 |
| 1 |
| 8 |
=1-
| 1 |
| 2 |
=
| 1 |
| 2 |
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