题目内容
计算下面各题,能用简便方法计算的要用简便方法计算.
|
(873×477-198)÷(476×874+199) | ||||||||||
| 199.9×19.98-199.8×19.97 |
|
(1)
×[
÷(
+
)],
=
×[
÷
],
=
×
,
=
;
(2)(873×477-198)÷(476×874+199),
=[873×(476+1)-198]÷[476×(873+1)+199],
=[873×476+873-198]÷[476×873+476+199],
=[873×476+675]÷[476×873+675],
=1;
(3)199.9×19.98-199.8×19.97,
=199.9×19.98-19.98×199.7,
=(199.9-199.7)×19.98,
=0.2×19.98,
=3.996;
(4)
×
+16×
+
×
,
=
×
+16×
+
×
,
=(
+
+16)×
,
=(4+16)×
,
=20×
,
=4.
| 8 |
| 9 |
| 3 |
| 7 |
| 2 |
| 3 |
| 1 |
| 7 |
=
| 8 |
| 9 |
| 3 |
| 7 |
| 17 |
| 21 |
=
| 8 |
| 9 |
| 9 |
| 17 |
=
| 8 |
| 17 |
(2)(873×477-198)÷(476×874+199),
=[873×(476+1)-198]÷[476×(873+1)+199],
=[873×476+873-198]÷[476×873+476+199],
=[873×476+675]÷[476×873+675],
=1;
(3)199.9×19.98-199.8×19.97,
=199.9×19.98-19.98×199.7,
=(199.9-199.7)×19.98,
=0.2×19.98,
=3.996;
(4)
| 4 |
| 5 |
| 12 |
| 13 |
| 1 |
| 5 |
| 1 |
| 5 |
| 4 |
| 13 |
=
| 1 |
| 5 |
| 48 |
| 13 |
| 1 |
| 5 |
| 1 |
| 5 |
| 4 |
| 13 |
=(
| 48 |
| 13 |
| 4 |
| 13 |
| 1 |
| 5 |
=(4+16)×
| 1 |
| 5 |
=20×
| 1 |
| 5 |
=4.
练习册系列答案
相关题目