Hỏi đáp về Nhân, chia số hữu tỉ - Đại số 7

tính

a) \(\left[\dfrac{0.8\div\left(\dfrac{4}{5}\cdot1025\right)}{0.64-1}+\dfrac{\left(1.08-\dfrac{2}{25}\right)\div\dfrac{4}{7}}{\left(6\dfrac{5}{7}-3\dfrac{1}{4}\right)\cdot2\dfrac{2}{17}}+\left(1.2\cdot0.5\right)\div\dfrac{4}{5}\right]\)

b) \(\left(0.2\right)^{-3}\left[\left(-\dfrac{1}{5}\right)^{-2}\right]^{-1}+\left[\left(\dfrac{1}{2}\right)^{-3}\right]^{-2}\div\left(2^{-3}\right)^{-1}-\left(0.175\right)^{-2}\)

c) \(2+\dfrac{1}{1+\dfrac{1}{2+\dfrac{1}{1+\dfrac{1}{2}}}}\)

d) \(\dfrac{1}{90}-\dfrac{1}{72}-\dfrac{1}{56}-\dfrac{1}{42}-\dfrac{1}{3}\)

e) \(\left(\dfrac{1}{3}\right)^{-1}-\left(-\dfrac{6}{7}\right)^0+\left(\dfrac{1}{2}\right)^2\div2\)

f) \(\dfrac{\dfrac{1}{3}-\dfrac{1}{7}-\dfrac{1}{13}}{\dfrac{2}{3}-\dfrac{2}{7}-\dfrac{2}{13}}\cdot\dfrac{\dfrac{3}{4}-\dfrac{3}{16}-\dfrac{3}{64}-\dfrac{3}{256}}{1-\dfrac{1}{4}-\dfrac{1}{16}-\dfrac{1}{64}}+\dfrac{5}{8}\)

g) \(\dfrac{1}{-\left(2017\right)\left(-2015\right)}+\dfrac{1}{\left(-2015\right)\left(-2013\right)}+...+\dfrac{1}{\left(-3\right)\cdot\left(-1\right)}\)

h) \(\left(1-\dfrac{1}{1\cdot2}\right)+\left(1-\dfrac{1}{2\cdot3}+...+\left(1-\dfrac{1}{2017\cdot2018}\right)\right)\)

tìm x

a) \(\dfrac{3}{7}x-\dfrac{2}{3}x=\dfrac{10}{21}\)

b) \(\dfrac{7}{35}:\left(x-\dfrac{1}{3}\right)=-\dfrac{2}{25}\)

a)\(\dfrac{\left(x+\dfrac{3}{4}\right)\cdot\dfrac{7}{2}-\dfrac{1}{6}}{-\left(\dfrac{4}{5}+\dfrac{1}{3}\right)\cdot\dfrac{1}{2}+1}=2\dfrac{33}{52}\)

b)\(\dfrac{\left(5-\dfrac{2}{7}\right)\cdot\dfrac{7}{9}:\dfrac{3}{5}}{\left(3x-\dfrac{5}{6}\right):\dfrac{1}{7}}=5\dfrac{5}{21}\)

Bài 7: Tìm X

a, \(\dfrac{2}{3}-\dfrac{2}{5}+\dfrac{2}{9}+\dfrac{2}{13}\)/\(\dfrac{11}{3}-\dfrac{11}{5}+\dfrac{9}{11}+\dfrac{11}{3}\)

Tìm x , biết ;

\(\dfrac{x+1}{2016}+\dfrac{x+2}{2015}=\dfrac{x+3}{2014}+\dfrac{x+4}{2013}\)

1 tính phép chia (x^2 - 16) : (x+4)
2 phân tích đa thức 8x^3 - 1

x/y=8/5; x/z=2/7 và x+y+z =27

heo me ToT

tính giá trị của mỗi biểu thức A,B,C,D rồi sắp xếp các kết quả tìm được theo thứ tự tăng dần

A=\(\dfrac{5}{4}.\left(5-\dfrac{4}{3}\right).\left(-\dfrac{1}{11}\right)\) B=\(\dfrac{3}{4}:\left(-12\right).\left(-\dfrac{2}{3}\right)\)

C=\(\dfrac{5}{4}:\left(-15\right).\left(-\dfrac{2}{5}\right)\) D=\(\left(-3\right).\left(\dfrac{2}{3}-\dfrac{5}{4}\right):\left(-7\right)\)

Tính:

M = 0,375 -0,3+3/11 +3/12 / -0,625 + 0,5 -5/11-5/12

Tính bằng cách hợp lí :

A=\(\dfrac{5}{9}:\left(\dfrac{1}{11}-\dfrac{5}{2}\right)+\dfrac{5}{9}:\left(\dfrac{1}{15}-\dfrac{2}{3}\right)\)

B=\(\left(6-\dfrac{2}{3}+\dfrac{1}{2}\right)-\left(5+\dfrac{5}{3}-\dfrac{3}{2}\right)-\left(3-\dfrac{7}{3}+\dfrac{5}{2}\right)\)

\(\dfrac{7}{3}:0.2x=\dfrac{7}{6}:0.8\)

Tìm

\(\dfrac{5}{9}:\left(\dfrac{1}{11}-\dfrac{5}{22}\right)+\dfrac{5}{9}:\left(\dfrac{1}{15}-\dfrac{2}{3}\right)\)

Tính: A= \(\left(1-\dfrac{1}{15}\right)\left(1-\dfrac{1}{21}\right)\left(1-\dfrac{1}{28}\right)...\left(1-\dfrac{1}{210}\right)\)

a \(\dfrac{5}{4}\).\(\dfrac{-12}{7}\)

b \(\dfrac{-4}{3}\):\(\dfrac{13}{9}\)

c \(\dfrac{-5}{7}\).\(\dfrac{49}{3}\):\(\dfrac{7}{-6}\)

d (\(-\dfrac{9}{25}\)):6

Tính giá trị:

P=\(\dfrac{0,75-0,6+\dfrac{3}{7}+\dfrac{3}{13}}{2,75-2,2+\dfrac{11}{7}+\dfrac{11}{3}}\)

Tìm tập hợp các số nguyên x thỏa mãn:
a) \(3\dfrac{1}{3}:2\dfrac{1}{2}-1< x< 7\dfrac{2}{3}.\dfrac{3}{7}+\dfrac{5}{2}\)
b) \(\dfrac{1}{2}-\left(\dfrac{1}{3}+\dfrac{1}{4}\right)< x< \dfrac{1}{48}-\left(\dfrac{1}{16}-\dfrac{1}{6}\right)\)
Help me.

(-4/5 +5/7) : 2/3 + ( -1/5 + 2/7) : 2/3 b) xác định điều kiện mà số hữu tỉ x phải thỏa mãn nếu

3/8 +x - hai và một phần ba ( hỗn số)

Các bợn giúp mình zới

Giúp tớ giải bài toán này với:

7/3:0,2x=7/6:0,8

Tính
\(a,\left(0,8.7+0.64\right).\left(1.25.7-\dfrac{4}{5}.1,25\right)\)
\(b,\dfrac{1}{4}-\dfrac{\dfrac{1}{4}+\dfrac{1}{9}}{\dfrac{1}{9}}\)
c,\(2\dfrac{1}{2}-3,4\left(12\right)-\dfrac{4}{3}+\dfrac{1}{3}.\left(\dfrac{1}{2}+0,5-3\dfrac{1}{2}\right)\)

Tìm x biết

\(\dfrac{7}{3}:0.2x=\dfrac{7}{6}:0.8\)

\(B=\dfrac{4}{9}:\left(\dfrac{1}{5}-\dfrac{2}{3}\right)+\dfrac{4}{9}:\left(\dfrac{1}{11}-\dfrac{5}{22}\right)\)

Tìm x ϵ N biết \(\dfrac{1}{4}.\dfrac{2}{6}.\dfrac{3}{8}.\dfrac{4}{10}......\dfrac{14}{30}.\dfrac{15}{32}=\dfrac{1}{2^x}\)

tìm x \(\in\) Z biết : ( x\(^2\) - 1 )( x\(^2\) - 4 )( x\(^2\) - 7 )( x\(^2\) - 10 ) < 0

tính hợp lí

a) \(\left(\dfrac{1}{7}-\dfrac{2}{5}\right).\dfrac{2016}{2017}+\left(\dfrac{13}{7}-\dfrac{2}{5}\right).\dfrac{2016}{2017}\)

b)\(\dfrac{1}{3}-\dfrac{3}{4}+\dfrac{3}{5}+\dfrac{2}{2015}-\dfrac{1}{36}+\dfrac{1}{15}-\dfrac{2}{9}\)

GIÚP MK VS

giúp mình tính nha ❤

a) (\(\dfrac{9}{25}\) -2 x 18 ):(\(3\dfrac{4}{5}\)+ 0.2 )

b) \(\dfrac{5^4.20^4}{25^5.4^5}\)