2 ) công các phân số sau ( rút gọn nếu có thể ) 
d ) \(\frac{7}{14}\) + \(\frac{9}{-36}\)

e ) \(\frac{-12}{32}\) + \(\frac{-21}{35}\)

f ) \(\frac{-15}{24}\) + \(\frac{18}{42}\) 

3) Tính 
a )\(\frac{-1}{24}\) + \(\frac{4}{16}\)

b )\(\frac{3}{16}\)+ \(\frac{5}{6}\)

4 ) So sánh 
a ) \(\frac{6}{7}\) và \(\frac{11}{10}\)

b ) - 5 / 17 và 2/7
c) 419/-723 và  - 699/-313 
Help me

a. \(\frac{3^2\times64^2-12^2\times16^2\times19+51\times33}{3+6+9+...+96+99}\)

b. \(\frac{6^3\times9^7\times4^3-16^2\times81^4}{\left(24\times3\right)^2}\)

c. \(\frac{21\times5^{21}\times5^8-25^{13}}{\left(4\times5^{14}\right)^2}\)

d. \(\frac{81^4\times3^{10}\times27^5\div3^{12}}{9^9\div9^3\times243^3}\)

e. \(\frac{18^6\div2^{11}\div9^3\times4^3}{32^2\div6^9\times3^6}\)
 

bài 1:thực hiện phép tính : 

a)\(\frac{3}{7}+\frac{5}{13}+\frac{4}{13}\)

b)\(\left(\frac{3}{8}+\frac{-3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)

c)\(\frac{2}{5}.\frac{1}{3}-\frac{2}{15}:\frac{1}{5}+\frac{3}{5}.\frac{1}{3}\)

d)\(\left(4-\frac{5}{12}\right):2+\frac{5}{24}\)

e)\(\frac{7}{19}.\frac{8}{11}+\frac{3}{11}.\frac{7}{19}+\frac{-1}{19}\)

f)\(\frac{9}{27}+\frac{8}{24}+\frac{18}{27}-\frac{-16}{24}+\frac{2}{3}\)

g)\(\frac{-5}{21}+\frac{-2}{21}+\frac{8}{24}\)

h)\(\frac{-5}{9}+\frac{8}{15}+\frac{-2}{11}+\frac{4}{-9}+\frac{7}{15}\)

i)\(\frac{7}{25}.\frac{39}{-14}.\frac{50}{78}\)

m.n làm nhanh cho mình nhé, chiều mình phải nộp rồi! cảm ơn m.n!

1. tính

a. \(\dfrac{3}{5}\)-\(\dfrac{2}{3}\)+\(\dfrac{16}{15}\)

b. (\(\dfrac{5}{6}\)-\(\dfrac{4}{5}\)):\(\dfrac{7}{30}\)-\(\dfrac{6}{7}\)

c. \(\dfrac{4}{11}\).\(\dfrac{-2}{9}\)+\(\dfrac{4}{11}\).\(\dfrac{-8}{9}\)+\(\dfrac{4}{11}\).\(\dfrac{1}{9}\)

d.\(\dfrac{-13}{10}\)-\(\dfrac{15}{16}\):\(\dfrac{-3}{4}\)+\(\dfrac{21}{25}\).\(\dfrac{-15}{28}\)

1Tính

.\(\frac{18,4.0,3.7,5.4,8}{2,5.4,6.9,6.0,9}\)

2.Tĩm x,y,z

\(\frac{x}{13}=\frac{-15}{39}=\frac{20}{y}\)

b.\(\frac{-7}{x}=\frac{14}{16}=\frac{y}{32}\)

c.\(\frac{24}{x}=\frac{y}{32}=\frac{-6}{z}=\frac{3}{2}\)

d.\(\frac{-10}{15}=\frac{x}{-9}=\frac{-8}{y}=\frac{z}{-21}\)

3.Tìm x, biết:

\(\frac{x+1}{6}=\frac{8}{3}\)

Mong các bạn giúp  mình! 

B1: Thực hiện phép tính :

a, \(11\frac{3}{4}-(6\frac{5}{6}-4\frac{1}{2})+1\frac{2}{3}\)

b, \(2\frac{17}{20}-1\frac{11}{5}+6\frac{9}{20}:3\)

c, \(4\frac{3}{7}:\left(\frac{7}{5}.4\frac{3}{7}\right)\)

d, \(\left(3\frac{2}{9}.\frac{15}{23}.1\frac{7}{29}\right):\frac{5}{23}\)

B2: Thực hiện phép tính:

\(a,11\frac{3}{4}-(6\frac{5}{6}4\frac{1}{2}+1\frac{2}{3})\\ b,\left(5\frac{7}{8}-2\frac{1}{4}-0,5\right):\frac{23}{26}\)

\(c,\left(17\frac{13}{15}-3\frac{3}{7}\right)-\left(2\frac{12}{15}-4\right)\\ d,2\frac{2}{3}.\frac{-4}{5}.0,375-\left(-10\right).\frac{-15}{24}\)

Thực hiện quy đồng mẫu các phân số sau:

a)\(\dfrac{2}{9}\); \(\dfrac{5}{18}\); \(\dfrac{1}{3}\) d) \(\dfrac{-4}{7}\); \(\dfrac{8}{9}\); \(\dfrac{-10}{21}\)

b) \(\dfrac{7}{15}\); \(\dfrac{1}{5}\);\(\dfrac{-5}{6}\) e) \(\dfrac{3}{-20}\); \(\dfrac{-11}{-30}\); \(\dfrac{7}{15}\)

c)\(\dfrac{-3}{16}\); \(\dfrac{5}{24}\); \(\dfrac{-21}{56}\)