a)=-4.25.-8.-125.-3

=-100.1000.-3

=300000

b)=-8.-125.25.-4.-9

=1000.-100.-9

=900000

c)=-4.-25.-9.7

=100.-63

=-6300

d) làm theo cách thường(ko chắc)

d biết rồi

biết rồi thì thôi

a) = \(\frac{-2}{5}\)

b) = \(\frac{-5}{4}\)

c)= \(\frac{-11}{15}\)

d) = \(\frac{3}{2}\)

a)-16/15.3/8=-2/5

b)51/2:(-42/5)=-255/84

c)=2/15

d)=3/2

a)-18/15.3/8=-2/5(rút gọn phân số thành tối giản nha bạn)

b)5 1/2:(-4 2/5)=11/2.-5/22=-5/4(làm như cách trên)

c)-5/4:25/8.-1/3=-5/4.8/25.-1/3=-2/5.-1/3=2/15

d)-1/5.-10/7:4/21=-2/7:4/21=-2/7.21/4=-3/2(Bài c và d cũng rút gọn phân số đến tối giản)

\(\dfrac{-8}{15}.\dfrac{3}{7}.\dfrac{15}{-8}.14=\left(\dfrac{-8}{15}.\dfrac{15}{-8}\right).\left(\dfrac{3}{7}.14\right)=1.6=6\)

\(\dfrac{17}{27}.\dfrac{13}{9}-\dfrac{4}{9}.\dfrac{17}{27}=\dfrac{17}{27}.\left(\dfrac{13}{9}-\dfrac{4}{9}\right)=\dfrac{17}{27}.1=\dfrac{17}{27}\)

1727.139−49.1727=1727.(139−49)=1727.1=1727

bài 1

a. = -10/3

b. = 14/5

c = 1/9

p = 1/9

bài 2.

a. x= 271/75

b. x = 1/3

bài 2

a. x - 10/3 = 7/15 . 3/5

    x - 10/3 = 7/25

           x   = 7/25 + 10/3

           x = 271/75

b. 8/23 . 46/24 - x = 1/3

               2/3 - x = 1/3

                      x = 2/3 - 1/3

                      x = 1/3

a. -5/2 : 3/4 = -5/2 . 4/3 = -20/6 = -10/3

b. (-3 1/7) : (-1 6/49) = -22/7 : (-55/49) = -22/7 . -49/55 = 1078/385 = 14/5

c. -1. 1/8 . 4/51 . (-11 1/3) = -1/8 . 4/51 . (-34/3) = -4/408 . (-34/13) = -1/102 . (-34/13) = 34/1326 = 1/39

d. (-1/6).(-15/19).38/45 = 15/114.38/45 = 5/38 . 38/45 = 5/45 = 1/9

`@` `\text {Ans}`

`\downarrow`

\(\dfrac{2^8-2^3}{2^5-1}=\dfrac{2^3\left(2^5-1\right)}{2^5-1}=\dfrac{2^3}{1}=2^3=8\)

_____

\(\dfrac{4^8\cdot9^4}{6^6\cdot8^3}\)

`=`\(\dfrac{\left(2^2\right)^8\cdot\left(3^2\right)^4}{2^6\cdot3^6\cdot\left(2^3\right)^3}\)

`=`\(\dfrac{2^{16}\cdot3^8}{2^6\cdot3^6\cdot2^9}\)

`=`\(\dfrac{2^{16}\cdot3^8}{2^{15}\cdot3^6}\)

`=`\(\dfrac{3^2}{2}\) `=`\(\dfrac{9}{2}\)

______

\(\dfrac{27^4\cdot2^3-3^{10}\cdot4^3}{6^4\cdot9^3}\)

`=`\(\dfrac{\left(3^3\right)^4\cdot2^3-3^{10}\cdot\left(2^2\right)^3}{2^4\cdot3^4\cdot\left(3^2\right)^3}\)

`=`\(\dfrac{3^{12}\cdot2^3-3^{10}\cdot2^6}{2^4\cdot3^4\cdot3^6}\)

`=`\(\dfrac{3^{10}\cdot\left(3^2\cdot2^3-2^6\right)}{3^{10}\cdot2^4}\)

`=`\(\dfrac{72-2^6}{2^4}=\dfrac{8}{16}=\dfrac{1}{2}\)

\(\dfrac{2^8-2^3}{2^5-1}=\dfrac{2^3\left(2^5-1\right)}{2^5-1}=2^3=8\)

\(\dfrac{4^8.9^4}{6^6.8^3}=\dfrac{2^{16}.3^8}{2^6.3^6.2^9}=2.3^2=18\)

\(\dfrac{27^4.2^3-3^{10}.4^3}{6^4.9^3}=\dfrac{3^{12}.2^3-3^{10}.2^6}{2^4.3^4.3^6}=\dfrac{2^3.3^{10}.\left(3^2-2^3\right)}{2^4.3^{10}}=\dfrac{9-8}{2}=\dfrac{1}{2}\)

\(x-\dfrac{3}{10}=\dfrac{7}{15}\cdot\dfrac{3}{5}\)

\(x-\dfrac{3}{10}=\dfrac{21}{75}\)

\(x=\dfrac{21}{75}+\dfrac{3}{10}\)

\(x=\dfrac{29}{50}\)

\(x-\dfrac{3}{10}=\dfrac{21}{75}\)

\(x=\dfrac{21}{75}+\dfrac{3}{10}\)

\(x=\dfrac{29}{50}\)

29/50