用递等式计算(能简算的请简算) ①7.6-4.8+8.4-5.2 ②4×0.8×2.5×1.25 ③79×1314+29÷1413

2025-05-16 18:30:53
推荐回答(1个)
回答1:

①7.6-4.8+8.4-5.2,
=(7.6+8.4)-(4.8+5.2),
=16-10,
=6;

②4×0.8×2.5×1.25,
=(4×2.5)×(0.8×1.25),
=10×1,
=10;

7
9
×
13
14
+
2
9
÷
14
13

=
7
9
×
13
14
+
2
9
×
13
14

=(
7
9
+
2
9
)×
13
14

=1×
13
14

=
13
14



④1375-375÷15×18,
=1375-25×18,
=1375-450,
=925;

⑤1.05×(3.8-0.8)÷6.3,
=1.05×3÷6.3,
=3.15÷6.3,
=0.5;

6
5
×[(
7
6
-
4
9
)÷
13
5
],
=
6
5
×[
39
54
÷
13
5
],
=
6
5
×
39
54
×
5
13

=
1
3