3.(x+1)-32=67
32 x 67 +32 x 2 - 32 x 2
= 32 x (67 + 2 - 2 ) = 32 x 67 = 2144
32 x 67 + 32 x 2 - 32 x 2
= 32 x (67+2-2)
=32 x 67
=2144
Bài 5. Tìm số nguyên x, biết:
1) 156 – (x + 32) = 115
2) (x – 34) - 97 = 0
3) 115 + (115 – x) = 215
4) 25 – 3.(6 – x) = 22
5) (x : 23 + 45) . 67 = 8911
2: \(\Leftrightarrow x-34=97\)
hay x=133
a,9x+67+32=100
b,87,75+95,5*x=87,75
c,(1*3x)*(2*3x)*(3*3x)*7=42
1) Chứn tỏ rằng:
a) 0,(32)+0,(67)=1
b) 0,(33)x3=1
@
2) Tìm x:
0,(12):1,(6)=x:0,(3)
1)
a)\(0,\left(32\right)+0,\left(67\right)\)
\(=0,\left(01\right).32+0,\left(01\right).67\)
\(=0,\left(01\right).\left(32+67\right)\)
\(=\frac{1}{99}.99\)
\(=1\left(đpcm\right)\)
b)\(0,\left(33\right).3\)
\(=0,\left(01\right).33.3\)
\(=\frac{1}{99}.33.3\)
\(=\frac{33}{99}.3\)
\(=\frac{99}{99}\)
\(=1\left(đpcm\right)\)
2)\(0,\left(12\right):1,\left(6\right)=x:0,\left(3\right)\)
\(\left[\left(0,01\right).12\right]:\left[1+0,\left(6\right)\right]=x:\left[0,\left(1\right).3\right]\)
\(\left(\frac{1}{99}.12\right):\left[1+0,\left(1\right).6\right]=x:\left(\frac{1}{9}.3\right)\)
\(\frac{4}{33}:\left[1+\frac{1}{9}.6\right]=x:\frac{1}{3}\)
\(\frac{4}{33}:\left[1+\frac{2}{3}\right]=x.3\)
\(3x=\frac{4}{33}:\frac{5}{3}\)
\(3x=\frac{4}{33}\cdot\frac{3}{5}\)
\(3x=\frac{4}{55}\)
\(x=\frac{4}{55}:3\)
\(x=\frac{4}{55}\cdot\frac{1}{3}\)
\(x=\frac{4}{165}\)
Tìm số trung bình cộng của các số sau:
1. 45, 32, 12, 67
2. 34, 67, 19
3. 40, 50, 60, 10, 30
1. Trung bình cộng của các số: ( 45+ 32+ 12+ 67) : 4= 39
2. Trung bình cộng của các số: ( 34+ 67 + 19) : 3= 40
3. Trung bình cộng của các số: ( 40 + 50 + 60 + 10 + 30) : 5= 38
Tôi học lớp 2A6.
Tìm x, biết:
a ) | x | = 4 − 3 + 7 4 ; b ) | x − 4 | = − 6 7 + 3 2 ; c ) x − 1 2 = − 7 10 + 9 4 ; d ) x − 7 9 = 7 12 + 5 3 − 11 4
a ) x = 5 12 x = − 5 12 b ) x = 89 14 x = 23 14
c ) x = 69 20 x = − 49 20 d ) x = 22 9 x = − 8 9
1) thực hiện phép tính
-126+67+[32-(-126)]-64
240-[(82-49):3+135]:18
A+1+2+22+23+...+22021
-205+37-(-200)
2) Tìm x∈z biết
x-45=48-68
35+5(6-x)=-12-(-112)
517-(x-124)=-483
46-(3x-2)3=(-38)+20
Bài 2:
a: =>x-45=-20
hay x=25
b: =>35+30-5x=-12+112
=>65-5x=100
=>5x=-35
hay x=-7
c: =>x-124=1000
hay x=1124
d: \(\Leftrightarrow46-\left(3x-2\right)^3=-18\)
\(\Leftrightarrow\left(3x-2\right)^3=64\)
=>3x-2=4
hay x=2
1) thực hiện phép tính
-126+67+[32-(-126)]-64
240-[(82-49):3+135]:18
A+1+2+22+23+...+22021
-205+37-(-200)
2) Tìm x∈z biết
x-45=48-68
35+5(6-x)=-12-(-112)
517-(x-124)=-483
46-(3x-2)3=(-38)+20
Bài 2:
a: =>x-45=-20
hay x=25
b: =>35+30-5x=-12+112=100
=>65-5x=100
=>5x=-35
hay x=-7
c: =>x-124=1000
hay x=1124
d: \(\Leftrightarrow46-\left(3x-2\right)^3=-18\)
\(\Leftrightarrow\left(3x-2\right)^3=64\)
=>3x-2=4
hay x=2
a ( -o, 75+ 1/2) ;4/3
b 7/5 , 7/4 -32/5
tim x
10/3,x + 67/4= -13,25
1) a) \(\left(-0,75+\frac{1}{2}\right):\frac{4}{3}\)
\(=\left(-0,75+\frac{1}{2}\right)\cdot\frac{3}{4}\)
\(=\left(-0,75+0,5\right)\cdot0,75\)
\(=-0,25\cdot0,75\)
\(=-0,1875\)
Vậy: \(\left(-0,75+\frac{1}{2}\right):\frac{4}{3}=-0,1875\)
b) \(\frac{7}{5}\cdot\frac{7}{4}-\frac{32}{5}\)
\(=\frac{49}{20}-\frac{32}{5}\)
\(=\frac{49}{20}-\frac{128}{20}\)
\(=-\frac{79}{20}=-3\frac{19}{20}\)
Vậy: \(\frac{7}{5}\cdot\frac{7}{4}-\frac{32}{5}=-3\frac{19}{20}\)
2) \(\frac{10}{3}\cdot x+\frac{67}{4}=-13,25\)
<=> \(\frac{10}{3}\cdot x+\frac{67}{4}=-\frac{53}{4}\)
<=> \(\frac{10}{3}\cdot x=-\left(\frac{53}{4}+\frac{67}{4}\right)\)
<=> \(\frac{10}{3}\cdot x=-30\)
<=> \(x=-30:\frac{10}{3}\)
<=> \(x=-30\cdot\frac{3}{10}\)
<=> \(x=-9\)
Vậy: \(x=-9\)