a) \(\dfrac{11\cdot8-11\cdot3}{17-6}\)

\(=\dfrac{11\cdot\left(8-3\right)}{11}=5\)

b) \(\dfrac{24-12\cdot13}{12+4\cdot9}\)

\(=\dfrac{12\cdot\left(2-13\right)}{12\left(1+3\right)}=\dfrac{-11}{4}\)

\(\dfrac{21\cdot9}{7\cdot6-7\cdot3}\\ =\dfrac{21\cdot9}{7\cdot\left(6-3\right)}\\ =\dfrac{21\cdot9}{7\cdot3}\\ =\dfrac{21\cdot9}{21}=9\)

mik cần gấp ak

a) \(\frac{3\cdot5\cdot7}{14\cdot55}=\frac{3\cdot5\cdot7}{2\cdot7\cdot11\cdot5}=\frac{3}{2\cdot11}=\frac{3}{22}\)

b) \(\frac{2^7\cdot3^4}{3^6\cdot2^5}=\frac{2^2\cdot2^5\cdot3^4}{3^2\cdot3^4\cdot2^5}=\frac{2^2}{3^2}=\frac{4}{9}\)

c) \(\frac{7\cdot9-7\cdot4}{14\cdot11-14}=\frac{7\left(9-4\right)}{14\cdot\left(11-1\right)}=\frac{7\cdot5}{14\cdot10}=\frac{7\cdot5}{2\cdot7\cdot2\cdot5}=\frac{1}{2\cdot2}=\frac{1}{4}\)

=7x(9+3+6+2+4)

=7x24

=........

=168 nho tích mình nha!

7​.9 + 7.3 + 7.6 + 7.2 + 7.4= 7.24 = 148

​

\(\dfrac{-33}{88}=\dfrac{-3}{8};11.8-\dfrac{11.3}{17-6}=88-\dfrac{33}{11}=88-3=85.\)

a)  − 7 .3 + 4. − 6 − 5 .3 + 2.3 = − 45 = 9 = 6

b)  3.6 + 2.9.5 − 18. − 4 7. − 7 + 12. − 7 + 7 = 18. 1 + 5 + 4 − 7 . 7 + 12 − 1 = 18.10 − 7.18 = − 10 7

Bài 1: 

a: =-3/7

b: =-3/5

c: =1/13

d: =-1/2

Bài 2: 

a: \(=\dfrac{21\cdot11}{22\cdot9}=\dfrac{1}{2}\cdot\dfrac{7}{3}=\dfrac{7}{6}\)

b: \(=\dfrac{49\cdot8}{10}=\dfrac{196}{5}\)

a \(\dfrac{-2}{5}\)

b -1

c \(\dfrac{2}{5}\)

d \(\dfrac{-18}{11}\)

a: \(=\dfrac{13\cdot\left(9-2\right)}{13}=7\)

b: \(=\dfrac{14\left(3-8\right)}{7\left(1+3\cdot3\right)}=2\cdot\dfrac{-5}{10}=-1\)

c: \(=\dfrac{54-72}{36}=\dfrac{-18}{36}=-\dfrac{1}{2}\)

d: \(=\dfrac{5^3}{10^2\cdot5}=\dfrac{5^2}{100}=\dfrac{1}{4}\)