| 神机妙算: 0.8×6.5-
| (
| 1-
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| 25×1.25×32 | 99×
| 1
|
| 4 |
| 5 |
=0.8×6.5-0.8×3.5,
=(6.5-3.5)×0.8,
=3×0.8,
=2.4;
(2)(
| 1 |
| 15 |
| 7 |
| 9 |
=
| 1 |
| 15 |
| 7 |
| 9 |
=3+35,
=38;
(3)1-
| 8 |
| 15 |
| 4 |
| 5 |
| 2 |
| 3 |
=1-
| 8 |
| 15 |
| 5 |
| 4 |
| 2 |
| 3 |
=1-
| 2 |
| 3 |
| 2 |
| 3 |
=1;
(4)25×1.25×32,
=25×1.25×8×4,
=25×4×(1.25×8),
=100×10,
=1000;
(5)99×
| 9 |
| 10 |
| 9 |
| 10 |
=(99+1)×
| 9 |
| 10 |
=100×
| 9 |
| 10 |
=90;
(6)1
| 9 |
| 14 |
| 7 |
| 8 |
| 1 |
| 8 |
=1
| 9 |
| 14 |
| 7 |
| 8 |
| 1 |
| 8 |
=1
| 9 |
| 14 |
=
| 9 |
| 14 |