99999999995=19999999999x5

=>\(\frac{\text{19999999999}}{99999999995}=\frac{\text{19999999999}}{\text{19999999999.5}}=\frac{1}{5}\)

1/5

1/5 chắc chắn luôn

1999999999/999999995=2 tích nha!

a.12/42

b.2.000000001

a)121212/424242=12/42=2/7

b)19999999999/99999999995=1/5

19999999999      1

------------------- =

99999999995      5

19999999999     1

-----------------=  ----

99999999995     5

\(\frac{8}{15}.\left(\frac{3333}{1212}+\frac{3333}{2020}+\frac{3333}{4242}+\frac{3333}{5656}\right)\)

= \(\frac{8}{15}.\left(\frac{11}{4}+\frac{33}{20}+\frac{11}{14}+\frac{33}{56}\right)\)

= \(\frac{8}{15}.\frac{231}{40}\)

= \(\frac{77}{25}\)

\(\frac{19999999999}{99999999995}\)

\(=\frac{19999999999:19999999999}{99999999995:19999999999}\)

\(=\frac{1}{5}\)

b) \(\frac{121212}{424242}=\frac{121212:60606}{424242:60606}=\frac{2}{7}\)

c) \(\frac{3.7.13.37.39-10101}{505050+707070}\)

\(=\frac{393939-10101}{1212120}\)

\(=\frac{383838}{1212120}\)

\(=\frac{19}{60}\)

ai biêt

chịu thua luôn 

\(\dfrac{50}{60}=\dfrac{5}{6}\)
\(\dfrac{33}{11}=3\)
\(\dfrac{16}{60}=\dfrac{4}{15}\)
\(\dfrac{42}{22}=\dfrac{21}{11}\)

chia là gì z

\(\dfrac{15}{90}=\dfrac{15:3}{90:3}=\dfrac{5}{30}=\dfrac{5:5}{30:5}=\dfrac{1}{6}\)

\(=>Phân.số.tối.giản.là:\dfrac{1}{6}.\)

\(\dfrac{21}{147}=\dfrac{21:7}{147:7}=\dfrac{3}{21}=\dfrac{3:3}{21:3}=\dfrac{1}{7}.\)

\(=>Phân.số.tối.giản.là:\dfrac{1}{7}.\)