Question

[tiết cẩm ly]

a ( -o, 75+ 1/2) ;4/3

b 7/5 , 7/4 -32/5  

tim x 

10/3,x + 67/4= -13,25

Answer 1

[Ngọc Lưu]

a. -3/16

b. -79/20

tìm x 

x=-9

Answer 2

[Nguyễn Thị Hồng Điệp]

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: \(x=-9\)