1 tấn = 1000 kg

1,5 tạ = 1,5 x 100 (kg) = 1500 kg

1km2 = 10 000 000 000 cm2

1dm = 10cm

2,6 tấn = 2600 kg

1 yến = 10 kg

1 km = 1000 m

700 m + 300 m = 1000 m = 1 km

1 tấn =1000kg

1,5 tạ=150kg

\(1\operatorname{km}^2=10000000000\operatorname{cm}^2\)

1dm=10cm

2,6 tấn=2600kg

1 yến=10kg

1km=1000m

700m+300m=1km

\(\left(1+x\right)+\left(2+x\right)+\left(3+x\right)+\)\(\left(4+x\right)+\left(5+x\right)=10\times5\)

\(\left(1+2+3+4+5\right)+\left(x+x+x+x+x\right)=50\)

\(15+5x=50\)

\(5x=35\)

\(x=7\)

Vậy \(x=7\)

\(\left(1+x\right)+\left(2+x\right)+\left(3+x\right)+\left(4+x\right)+\left(5+x\right)=10\times5\)

\(\Rightarrow1+x+2+x+3+x+4+x+5+x=50\)

\(\Rightarrow\left(1+2+3+4+5\right)+\left(x+x+x+x+x\right)=50\)

\(\Rightarrow15+5x=50\)

\(\Rightarrow5x=50-15\)

\(\Rightarrow5x=35\)

\(\Rightarrow x=35:5\)

\(\Rightarrow x=7\).

  \(x(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{132}=\) \(5\frac{1}{2}\)        

 \(x\left(\frac{1}{1\cdot2}+\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+...+\frac{1}{11\cdot12}\right)=\frac{11}{2}\)

 \(x\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{11}-\frac{1}{12}\right)=\frac{11}{2}\)

 \(x\left(1-\frac{1}{12}\right)=\frac{11}{2}\)

 \(x\cdot\frac{11}{12}=\frac{11}{2}\)

 \(x=\frac{11}{2}:\frac{11}{12}\)

\(x=6\)

Vậy x = 6

\(\frac{x}{2}+\frac{x}{6}+\frac{x}{12}+\frac{x}{20}+...+\frac{x}{132}=5\frac{1}{2}\)

\(\Rightarrow x\left(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{132}\right)=\frac{11}{2}\)

\(\Rightarrow x\left(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{11.12}\right)=\frac{11}{2}\)

\(\Rightarrow x\left(\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{11}-\frac{1}{12}=\frac{11}{2}\right)\)

\(\Rightarrow x\left(1-\frac{1}{12}\right)=\frac{11}{2}\)

\(\Rightarrow x.\frac{11}{12}=\frac{11}{12}\)

\(\Rightarrow x=\frac{11}{12}:\frac{11}{12}=1\)

Vậy x = 1

  x ×(3+5+7+9+...+19)=297

x × 99 =297

x =297:99

x=3

giúp nốt câu này nhé mn ( T^T)

x : 0,25 + x :0,5 + x + x : 0,01 = 321

x nhân 4 + x nhân 2 + x nhân 1 nhân 100 = 321

x nhân (4 +2 +1 +100) = 321

x nhân 107 = 321

x = 321:107

x = 3

Zậy x = 3

 Đáp án : 

 x = 0 

 Nhớ tích ~ !!! Thanks !!

theo mik x=0

hok tốt

a) \(\frac{1}{3}-\frac{2}{x}=\frac{1}{6}\)

=> \(\frac{2}{x}=\frac{1}{3}-\frac{1}{6}\)

=> \(\frac{2}{x}=\frac{1}{6}\)

\(\Rightarrow x=12\)

Vậy x = 12

b) \(\frac{x-1}{2}=\frac{3}{4}\)

\(\Rightarrow\left(x-1\right).4=2.3\)

=> 4x - 4 = 6

=> 4.(x-1) = 6

=> x-1 = 6:4  = 1,5

=> x = 1,5 + 1

=> x = 2,5

Vậy x = 2,5

a,12

b,7

\(x:10+x.3,9=48\)

\(\Leftrightarrow x.0,1+x.3,9=48\)

\(\Rightarrow x\left(0,1+3,9\right)=48\)

\(\Rightarrow x.4=48\)

\(\Rightarrow x=48:4\)

\(\Rightarrow x=12\)

Vậy số cần tìm là 12

~Study well~

#Bạch_Dương_Chi#

#)Giải :

\(x\): 10  +  \(x\)x  3,9  =  48

\(x\)x 0,1 + \(x\)x  3,9  = 48

\(x\)x  (  0,1 + 3,9 )      = 48

\(x\)x   4                     = 48

\(x\)                            = 48 : 4

\(x\)                            = 12

               ~Will~be~Pens~

a)Ta có: \(\frac{x.5}{x}=5\)

\(\Rightarrow\frac{x}{x}.5=5\)

\(\Rightarrow\frac{x}{x}=5:5=1\)

\(\Rightarrow\) với mọi giá trị, x đều thỏa mãn cho điều kiện \(\frac{x}{x}=1\)

b)\(\frac{x}{x.3}=\frac{1}{3}\)

\(\Rightarrow\frac{x}{x}.\frac{1}{3}=\frac{1}{3}\)

\(\Rightarrow\frac{x}{x}=\frac{1}{3}:\frac{1}{3}=\frac{1}{3}.3=1\)

\(\Rightarrow\)với mọi giá trị, x đều thỏa mãn cho điều kiện \(\frac{x}{x}=1\)

(178 + 2) : 6 = 30

x = 178 nhé