456.(-25) 25.356
Tính bằng cách thuận tiện nhất: 456 x 65 + 456 x 25 + 456 x 10
( trình bày chi tiết các bước giải)
456 x 65 + 456 x 25 + 456 x 10
=456x(65+25+10)
=456x100
=45 600
\(a.25\) x \(432\) x \(4\) \(=\)
\(b.456 \) x \(200-\) \(456\) x \(100=\)
`a)25xx532xx4`
`=(25xx4)xx432`
`=432xx100=43200`
`b)456xx200-456xx100`
`=456xx(200-100)`
`=456xx100=45600`
\(a,25\times432\times4=25\times4\times432=100\times432=4320\\ b,456\times200-456\times100=456\times\left(200-100\right)=456\times100=45600\)
`25 xx 432 xx 4 = (25xx4 ) xx 432 = 100 xx 432 = 43200`
`456 xx200 - 456 xx 100 = 456 xx ( 200 - 100 ) = 456 xx 100 = 45600`
25 * 432 * 4 =
456 * 200 - 456 * 100 =
tính bằng cách thuận tiện nhất
25 x 432 x 4
=( 25 x 4 )x 432
= 100 x 432
= 43 200
456 x 200 - 456 x 100
= 456 x ( 200 - 100)
= 456 x 100
= 45 600
bài 1:Tính nhanh
a,64*25+35*25+25
b,58*42+32*8+5*16
c,(42*43+43*57+43)-360/4
d,(372-19*4)+(981/9-13)
e,456/2*8+456/3-102
a)2500
b)2772
c)1974
d)347
e)1874
k mk nha
a)64.25+35.25=25
b)58.42+32.8+5.16
c)42.43+43+57.43
d)456:2 nhân 18+456:3-102
Tìm N,x biết:
[(123x-456)]+25=1256
[(123x-456)]+25=1256
=>123x-456=1231
=>123x=1687
=>x=1687/123
\(\left[\left(123x-456\right)\right]+25=1256\)
\(123x-456=1231\)
\(123x=1231+456\)
\(123x=1687\)
\(x=1687:123\)
\(x=13\frac{88}{123}\)
Vậy \(x=13\frac{88}{123}\)
Tìm x. Biết [(250-25):15]:x=(456-60):130
Tính bằng hai cách:
a,(75+25):5
b,(84-24):4
c,(123+456):3
d,(936-306):6
\(a,C1:\left(75+25\right):5=100:5=20\\ C2:\left(75+25\right):5=75:5+25:5=15+5=20\)
\(b,C1:\left(84-24\right):4=60:4=15\\ C2\left(84-24\right):4=84:4-24:4=21-6=15\)
\(c,C1:\left(123+456\right):3=579:3=193\\ C2:\left(123+456\right):3=123:3+456:3=41+152=193\)
\(d,C1:\left(936-306\right):6=630:6=105\\C2:\left(936-306\right) :6=936:6-306:6=156-51=105\)
a,(75 + 25) : 5
C1: 100 : 5 = 20
C2: 75 : 5 + 25 : 5 = 15 + 5 = 20
b,(84 - 24) : 4
C1: 60 : 4 = 15
C2: 84 : 4 - 24 : 4 = 21 - 6 = 15
c,(123 + 456) : 3
C1: 579 : 3 = 193
C2: 123 : 3 + 456 : 3 = 41 + 152 = 193
d,(936 - 306) : 6
C1: 630 : 6 = 105
C2: 936 : 6 - 306 : 6 = 156 - 51 = 105
A,123:25=
B.789:93=
C,121:82=
D,456:78=
A,123:25=4,92
B.789:93=\(\frac{263}{31}\)
C,121:82=\(\frac{121}{82}\)
D,456:78=\(\frac{76}{13}\)
hok tốt .
123:25=4,92
789:93=4,483870968
121:82=1,475609756
456:78=5,846153846
Đáp số ..............