小学四年级:递等式计算

来源:百度知道 编辑:UC知道 时间:2024/05/27 14:26:25
1.340÷5+340÷5
2.55×101-55+16×25
3.8421-277-623+579
4.(364-456)-(544-636)
5.62×4+44×5+5×18
6.6200÷124
7.(7500÷15)÷(25×2)
8.3400-62×34-38×20-38×14

有些可以巧算,有些不可以巧算,最好巧算哦,拜托了!!快啊
现在都要巧算~~~~

1.
340÷5+340÷5
=68+68
=136

2.
55×101-55+16×25
=55×(100+1)-55+400
=5500+55-55+400
=5900

3.
8421-277-623+579
=8421+579-(277+623)
=9000-900
=8100

4.
(364-456)-(544-636)
=364-456-544+636
=364+636-(456+544)
=1000-1000
=0

5.
62×4+44×5+5×18
=62×4+5×(44+18)
=62×4+5×62
=62(4+5)
=62*9
=558

6.
6200÷124
=50

7.
(7500÷15)÷(25×2)
=500÷50
=10

8.
3400-62×34-38×20-38×14
=3400-62×34-38(20+14)
=3400-62×34-38×34
=3400-34(62+38)
=3400-34*100
=3400-3400
=0

(1) =68+68
=136

(2) =5555-55+400
=5500+400
=5900

(3) =8144-623+579
=7521+579
=8100

(4) =-92-(-92)
=0

(5) =248+220+90