题目内容
计算
(1)
÷
×
(2)(
+
)÷
(3)
×
+
÷4
(4)1836÷[56×(
-
)]
(5)50.7÷[(
-
)×24]
(6)有一种数学运算符号*,使下列等式成立:2*4=12,5*3=18,9*7=70.请计算8*8.
(1)
| 2 |
| 9 |
| 8 |
| 27 |
| 2 |
| 15 |
(2)(
| 1 |
| 4 |
| 3 |
| 10 |
| 3 |
| 4 |
(3)
| 5 |
| 6 |
| 1 |
| 4 |
| 1 |
| 6 |
(4)1836÷[56×(
| 4 |
| 7 |
| 1 |
| 4 |
(5)50.7÷[(
| 5 |
| 6 |
| 1 |
| 4 |
(6)有一种数学运算符号*,使下列等式成立:2*4=12,5*3=18,9*7=70.请计算8*8.
分析:(1)、(2)、(3)、(4)、(5)根据四则运算的运算顺序知道,先算小括号,再算乘除,最后算加减;注意运算过程中的简算;
(2)根据所给出的式子,得出新的运算方法,即b*a等于a与b的积再加a,由此利用新的运算方法解决问题.
(2)根据所给出的式子,得出新的运算方法,即b*a等于a与b的积再加a,由此利用新的运算方法解决问题.
解答:解:(1)1)
÷
×
,
=
×
×
,
=
,
(2)(
+
)÷
,
=
÷
,
=
×
,
=
,
(3)
×
+
÷4,
=
×
+
×
,
=
×(
+
),
=
×
,
=
,
(4)1836÷[56×(
-
)],
=1836÷[56×
-56×
],
=1836÷18,
=102,
(5)50.7÷[(
-
)×24],
=50.7÷[
×24-
×24],
=50.7÷14,
=
,
(6)2*4=12=2×4+4,5*3=18=5×3+3,9*7=70=9×7+7.
所以8*8=8×8+8=72,
故答案为:
,
,
,102,
,72.
| 2 |
| 9 |
| 8 |
| 27 |
| 2 |
| 15 |
=
| 2 |
| 9 |
| 27 |
| 8 |
| 2 |
| 15 |
=
| 1 |
| 10 |
(2)(
| 1 |
| 4 |
| 3 |
| 10 |
| 3 |
| 4 |
=
| 11 |
| 20 |
| 3 |
| 4 |
=
| 11 |
| 20 |
| 4 |
| 3 |
=
| 11 |
| 15 |
(3)
| 5 |
| 6 |
| 1 |
| 4 |
| 1 |
| 6 |
=
| 1 |
| 6 |
| 5 |
| 4 |
| 1 |
| 6 |
| 1 |
| 4 |
=
| 1 |
| 6 |
| 5 |
| 4 |
| 1 |
| 4 |
=
| 1 |
| 6 |
| 3 |
| 2 |
=
| 1 |
| 4 |
(4)1836÷[56×(
| 4 |
| 7 |
| 1 |
| 4 |
=1836÷[56×
| 4 |
| 7 |
| 1 |
| 4 |
=1836÷18,
=102,
(5)50.7÷[(
| 5 |
| 6 |
| 1 |
| 4 |
=50.7÷[
| 5 |
| 6 |
| 1 |
| 4 |
=50.7÷14,
=
| 507 |
| 140 |
(6)2*4=12=2×4+4,5*3=18=5×3+3,9*7=70=9×7+7.
所以8*8=8×8+8=72,
故答案为:
| 1 |
| 10 |
| 11 |
| 15 |
| 1 |
| 4 |
| 507 |
| 140 |
点评:此题主要考查了四则运算的计算顺序,注意能简算的要简算.
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