a) \(\dfrac{10}{20}=\dfrac{10:10}{20:10}=\dfrac{1}{2}\)

\(\dfrac{12}{72}=\dfrac{12:12}{72:12}=\dfrac{1}{6}\)

\(\dfrac{14}{42}=\dfrac{14:14}{42:14}=\dfrac{1}{3}\)

\(\dfrac{25}{100}=\dfrac{25:25}{100:25}=\dfrac{1}{4}\)

b) \(\dfrac{1010}{1313}=\dfrac{1010:101}{1313:101}=\dfrac{10}{13}\)

\(\dfrac{1111}{1414}=\dfrac{1111:101}{1414:101}=\dfrac{11}{14}\)

c) \(\dfrac{143}{154}=\dfrac{143:11}{154:11}=\dfrac{13}{14}\)

\(\dfrac{990}{2610}=\dfrac{990:90}{2610:90}=\dfrac{11}{29}\)

\(\dfrac{374}{506}=\dfrac{374:22}{506:22}=\dfrac{17}{23}\)

\(a)\dfrac{10}{20}=\dfrac{1}{2};\dfrac{12}{72}=\dfrac{1}{6};\dfrac{14}{42}=\dfrac{1}{3};\dfrac{25}{100}=\dfrac{1}{4}\)

\(b)\dfrac{1010}{1313}=\dfrac{10}{13};\dfrac{1111}{1414}=\dfrac{11}{14}\)

\(c)\dfrac{143}{154}=\dfrac{13}{14};\dfrac{990}{2610}=\dfrac{11}{29};\dfrac{374}{506}=\dfrac{17}{23}\)

Chúc bn học tốt !!!

giup mk voi

a,999/2610=111/290

b,374/506=17/23

c,3600-75/8400-175=3/7

d,9^14.25^5.8^7/18^12.625^3.24^3=3/25

a, Ta có:999/2610=111/290

b, Ta có:374/506=17/2

c,Ta có:3600-75/8400-175=48.75-75/48.175-175=75.(48-1)/175.(48-1)=75/175=3/7

d, Ta có:(3^2)^14.(5^2)^5.(2^3)^7/(2.3^2)^12.(5^4)^3.(2^3.3)^3

=3^28.5^10.2^21/2^12.3^24.5^12.2^9.3^3

=3^28.5^10.2^21/2^21.3^27.5^12

=3/5^2=3/25

\(\frac{18.2+9}{27}=\frac{9.2.2+9}{3.9}=\frac{9\left(2.2+1\right)}{3.9}\)

\(\Rightarrow\frac{2.2+1}{3}=\frac{5}{3}\)

             \(\frac{27.2}{27}=1,00740741\)

136 phần 135

dễ lắm mà

ừa, nhưng mik còn những câu sau khó hơn nhưng mỏi tay quá nên tí gửi tiếp!

a,=-36/7

b,=11/29

c,=17/23

d,=3/7

e,=-5/9

a) Ta có : 

990 = 2.3².5.11

2610=2.3².5.29

ƯCLN(990;2610) = 2.3².5=90

\(\Rightarrow\frac{990}{2610}=\frac{990:90}{2610:90}=\frac{11}{29}\)

Tương tự với câu b) 

\(a,\frac{990}{2610}=\frac{990:90}{2610:90}=\frac{11}{29}\)

\(b,\frac{374}{506}=\frac{374:2}{506:2}=\frac{187}{253}=\frac{187:11}{253:11}=\frac{17}{23}\)

\(c,\frac{3600-75}{8400-175}=\frac{3525}{8225}=\frac{3525:25}{8225:25}=\frac{141}{329}\)

\(d,\frac{9^{14}.25^5.8^7}{18^{12}.625^3.24^3}=\frac{9^{12}.9^2.25^3.25^2.8^3.8^4}{\left(9.2\right)^{12}.\left(25.25\right)^3.\left(8.3\right)^3}=\frac{9^{12}.9^2.25^3.25^2.8^3.8^3.8}{9^{12}.2^{12}.25^3.25^2.25.8^3.3^3}=\frac{9^2.8}{2^{12}.25.3^3}\) đến đây bn tự làm nốt đi! 

~ mỏi ~

lấy bài của chị đúng ko em

\(\frac{44116-14}{10290-35}=\frac{44102}{10255}\)

\(\frac{3600-75}{8400-175}=\frac{75\left(48-1\right)}{35\left(240-5\right)}=\frac{15\cdot47}{7\cdot235}=\frac{3\cdot5\cdot47}{7\cdot5\cdot47}=\frac{3}{7}\)

g, \(\frac{44116-14}{10290-35}=\frac{44102}{10255}\)

h, \(\frac{3600-75}{8400-175}=\frac{3525}{8225}=\frac{3}{7}\)

\(\frac{-72}{14}=\frac{-36}{7}\)

\(\frac{990}{2610}=\frac{11}{29}\)

\(\frac{374}{506}=\frac{17}{23}\)

\(\frac{3600-75}{8400-175}=\frac{3525}{8225}=\frac{3}{7}\)

hok tốt!!