Bài 1: Thực hiện phép tính:
a, \(\left(\dfrac{7}{20}+\dfrac{11}{15}-\dfrac{15}{12}\right):\left(\dfrac{11}{20}-\dfrac{26}{45}\right)\)
b, \(\dfrac{5-\dfrac{5}{3}+\dfrac{5}{9}-\dfrac{5}{27}}{8-\dfrac{8}{3}+\dfrac{8}{9}-\dfrac{8}{27}}:\dfrac{15-\dfrac{15}{11}+\dfrac{15}{121}}{16-\dfrac{16}{11}+\dfrac{16}{121}}\)
c, \(\dfrac{\dfrac{1}{9}-\dfrac{5}{6}-4}{\dfrac{7}{12}-\dfrac{1}{36}-10}\)
Thực hiện phép tính
a) \(\dfrac{1}{2}.\left(\dfrac{2}{9}+\dfrac{3}{7}-\dfrac{5}{27}\right)\) b) \(\left(\dfrac{-5}{28}+1,75+\dfrac{8}{35}\right):\left(-3\dfrac{9}{20}\right)\)
c) \(\dfrac{1}{3}.\dfrac{5}{7}-\dfrac{7}{27}.\dfrac{36}{14}\) d) \(70,5-528:\dfrac{15}{2}\)
Cho C= \(4+\dfrac{1}{7^6}+\dfrac{3}{7}+\dfrac{4}{7^2}+\dfrac{-441}{7^6}+\dfrac{27}{7^5}\)
D= \(\dfrac{147}{7^3}+4+\dfrac{35}{7^7}+\dfrac{4}{7^2}+\dfrac{27}{7^5}+\dfrac{-9}{7^9}\)
So sánh C với D
A=15.\(\left(\dfrac{3}{5}-\dfrac{2}{3}\right)+1\)
\(B=1-\dfrac{13}{9}:\dfrac{8}{19}+\dfrac{-11}{9}:\dfrac{8}{19}\)
\(C=\dfrac{-5}{7}.\dfrac{2}{11}+\dfrac{-5}{7}.\dfrac{9}{11}+1\dfrac{5}{7}\)
\(D=\dfrac{6}{7}+\dfrac{5}{8}:5-\dfrac{3}{16}.\left(-2\right)^2\)
tính giá trị của biểu thức
tính
a,\((15.\dfrac{3}{5}-19\dfrac{7}{9})-(13\dfrac{3}{5}-17\dfrac{7}{9})\)
b,\([\dfrac{6}{5}-(\dfrac{3}{7}-2\dfrac{1}{7})\div\dfrac{4}{7}].(-\dfrac{3}{5})+\dfrac{2}{3}\div(-\dfrac{5}{6})\)
giúp mình nhé
Tìm x \(\in\) Z biết;
a) \(\dfrac{x}{15}=\dfrac{4}{y}=\dfrac{-2}{5}\)
b) \(\dfrac{x-3}{4}=\dfrac{15}{20}\)
c) \(\dfrac{-5}{9}+\dfrac{-8}{15}+\dfrac{22}{-9}+\dfrac{-7}{15}< x\le\dfrac{-1}{3}+\dfrac{-1}{4}+\dfrac{-5}{12}\)
BT2: Tính nhanh
9) (\(\left(5+\dfrac{1}{5}-\dfrac{2}{9}\right)-\left(2-\dfrac{1}{23}-2\dfrac{3}{35}+\dfrac{5}{6}\right)-\left(8+\dfrac{2}{7}-\dfrac{1}{18}\right)\)
10)\(\dfrac{1}{3}-\dfrac{3}{4}-\left(-\dfrac{3}{5}\right)+\dfrac{1}{64}-\dfrac{2}{9}-\dfrac{1}{36}+\dfrac{1}{15}\)
Bài 3: Tính(hợp lí nếu có thể)
a) \(\dfrac{-7}{9}\)+\(\dfrac{5}{12}\)-\(\dfrac{13}{18}\)
b)\(\dfrac{11}{9}\)x\(\dfrac{15}{4}\)-\(\dfrac{11}{4}\)x\(\dfrac{7}{9}\)-\(\dfrac{11}{9}\)x\(\dfrac{5}{4}\)
c)(\(15\dfrac{9}{7}\)+\(6\dfrac{2}{3}\))-\(5\dfrac{5}{9}\)
d)\(\dfrac{5}{6}\)-\(\dfrac{1}{3}\)-\(\dfrac{2}{-18}\)
e)(\(6\dfrac{4}{9}\)+\(3\dfrac{7}{11}\))-\(4\dfrac{4}{9}\)
f)(\(11\dfrac{2}{7}\)+\(3\dfrac{2}{5}\))-\(7\dfrac{2}{7}\)
Tính
\(\dfrac{7}{9}:\left(2+\dfrac{3}{4}x\right)+\dfrac{5}{9}=\dfrac{23}{27}\)