题目内容
| 估算(写出必要的估算过程) 671×18-974 | 58.7-16.05÷3.7 |
| 8.2×1.6-16.3÷4.2 | 30.3÷[14-(9.85+1.07)]. |
(1)671×18-974,
≈670×20-1000,
=13400-1000,
=12400;
(2)58.7-16.05÷3.7,
≈60-16÷4,
=60-4,
=56;
(3)8.2×1.6-16.3÷4.2,
≈8×2-16÷4,
=16-4,
=12;
(4)30.3÷[14-(9.85+1.07)].
≈30÷[14-(10+1)],
=30÷[14-11],
=30÷3,
=10.
≈670×20-1000,
=13400-1000,
=12400;
(2)58.7-16.05÷3.7,
≈60-16÷4,
=60-4,
=56;
(3)8.2×1.6-16.3÷4.2,
≈8×2-16÷4,
=16-4,
=12;
(4)30.3÷[14-(9.85+1.07)].
≈30÷[14-(10+1)],
=30÷[14-11],
=30÷3,
=10.
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