Question

tìm x

a)   x+x* 1/3 : 2/9 + x :2/7= 252

b)   (x+2)+ (x+5)+(x+8)+...+(x+32)=198

Answer 1

Ta có : (x + 2) + (x + 5) + (x + 8) + ...... + (x + 32) = 198

<=> (x + x + x + ...... + x) + (2 + 5 + 8 + ....... + 32) = 198

<=> 11x + 187 = 198

=> 11x = 198 - 187

=> 11x = 11

=> x = 1

Answer 2

a . 

 \(x+x\times\frac{1}{3}\div\frac{2}{9}+x\div\frac{2}{7}=252\)

\(x+x\times\frac{3}{2}+x=252\times\frac{2}{7}\)

\(x+x\times\frac{3}{2}+x=72\)

\(x=72\div\frac{3}{2}-3x\)

\(x=48-3x\)

\(x=45\)

Answer 3

\(\left(x+2\right)+\left(x+5\right)+\left(x+8\right)+....\left(x+32=198\right)\)

Answer 4

b, (x + 2) + (x + 5) + (x + 8) + .........+ (x + 32) = 198 

=> (x + x + x +...+ x) + (2 + 5 + 8 + .. + 32) = 198 

=> số số x là: (32 - 2) : 3 + 1 = 11 

=> Tổng là: (2 + 32) x 11 : 2 = 187 

Ta có: 

187 + 11x = 198 

11x = 198 - 187 = 11

=> x = 11 : 11 

=> x = 1 

Answer 5

a , \(x+x\times\frac{1}{3}.\frac{2}{9}+x:\frac{2}{7}=252\)

\(x+x\times\frac{3}{2}+x-252\times\frac{2}{7}\)

\(x+x\times\frac{3}{2}+x=72\)

\(x=72:\frac{3}{2}-3x\)

\(x=48-3x\)

\(x=45\)

b , \(\left(x+2\right)+\left(x+5\right)+\left(x+8\right)+....+\left(x+32\right)\)\(=198\)

<=> \(\left(x+x+x+...+x\right)+\left(2+5+8+...+32\right)\)\(=198\)

<=> \(11x+187=198\)

=> \(11x=198-187\)

=> \(11x=11\)

=> \(x=11:11\)

=> \(x=1\)