chỉ giùm mk những bài này nha
bài 1 thực hiên phép tính sau
a)750chia{5.[325-(290+15)]}
b)321-21.[(2.3mu 3+4 mu 4 chia 32)-52]
c)18 chia {240 chia [280 -(80+32.5)]}
bài 2 tìm x bt
a)125+(x-110)=150
b)(2x +1)-7=14
c)200-8(2x+7)=112
d)5 mu x =125
e)x mu 13chia 3 mu 7=3 mu 6
f)3 mu x+3 mu x +1=324
bài 4 tinh nhanh
a)4.8.25.97.125
b)47.54+47.45+47
c)235.284-235.83-235
giúp mk nha
Bài 1:
a)750:{5.[325-(290+15)]}
=750:{5[325-275]}
=750:{5.50}
=750:250
=3
c)18:{240:[280-(80+32.5)]}
=18:{240:[280-(80+160)]}
=18:{240:[280-240]}
=18:{240:40}
=18:6
=3
Bài 2:
a)125+(x-110)=150
x-110=150-125
x-110=25
x =25+110
x =125
Vậy x =125
b)(2x +1)-7=14
2x+1 =14+7
2x+1 =21
2x=21-1
2x=20
x=20:2
x=2
Vậyx=2
c)200-8(2x+7)=112
8(2x+7)=200-112
8(2x+7)=88
2x+7 =88:8
2x+7=11
2x=11-7
2x=4
x=4:2
x=2
Vậyx=2
Bài 4:
a)4.8.25.97.125
=(4.25)(8.125)97
=100.1000.97
=9700000
b)47.54+47.45+47
=47(54+45+1)
=47.100
=4700
c)235.284-235.83-235
=235(284-83-1)
=235.200
=47000
Bài 1:
a)750:{5.[325-(290+15)]}
=750:{5[325-275]}
=750:{5.50}
=750:250
=3
b)321-21.[(2.3³+$4^{4}$:32)-52]
=321-21[(54+8)-52]
=321-21[62-52]
=321-21.10
=321-210
=111
c)18:{240:[280-(80+32.5)]}
=18:{240:[280-(80+160)]}
=18:{240:[280-240]}
=18:{240:40}
=18:6
=3
Bài 2:
a)125+(x-110)=150
x-110=150-125
x-110=25
x =25+110
x =125
Vậy x =125
b)(2x +1)-7=14
2x+1 =14+7
2x+1 =21
2x=21-1
2x=20
x=20:2
x=2
Vậyx=2
c)200-8(2x+7)=112
8(2x+7)=200-112
8(2x+7)=88
2x+7 =88:8
2x+7=11
2x=11-7
2x=4
x=4:2
x=2
Vậyx=2
d)$5^{x}$=125
$5^{x}$=5³
⇒x=3
Vậy x=3
Bài 4:
a)4.8.25.97.125
=(4.25)(8.125)97
=100.1000.97
=9700000
b)47.54+47.45+47
=47(54+45+1)
=47.100
=4700
c)235.284-235.83-235
=235(284-83-1)
=235.200
=47000
@nguyễn