a) $\frac{4.7}{9.32}=\frac{4.7}{\mathrm{9.4.8}}=\frac{7}{9.8}=\frac{7}{72}$

b) $\frac{3.21}{14.15}=\frac{\mathrm{3.3.7}}{\mathrm{2.7.3.5}}=\frac{3}{2.5}=\frac{3}{10}$

c) $\frac{\mathrm{2.5.13}}{26.35}=\frac{\mathrm{2.5.13}}{\mathrm{2.13.5.7}}=\frac{1}{7}$

d) $\frac{9.6–9.3}{18}=\frac{9.(6–3)}{9.2}=\frac{6–3}{2}=\frac{3}{2}$

e) $\frac{17.5–17}{3–20}=\frac{17.(5–1)}{–17}=\frac{5–1}{–1}=–4$

f) $\frac{49+7.49}{49}=\frac{49.(1+7)}{49}=1+7=8$

a) \(\dfrac{4.7}{9.32}=\dfrac{4.7}{9.4.8}=\dfrac{7}{72}\)

b) \(\dfrac{3.21}{14.15}=\dfrac{3.3.7}{2.7.3.5}=\dfrac{3}{10}\)

c) \(\dfrac{2.5.13}{26.35}=\dfrac{2.5.13}{2.13.5.7}=\dfrac{1}{7}\)

d) \(\dfrac{9.6-9.3}{18}=\dfrac{9\left(6-3\right)}{9.2}=\dfrac{3}{2}\)

e) \(\dfrac{17.5-17}{3-20}=\dfrac{17\left(5-1\right)}{-17}=\dfrac{5-1}{-1}=-4\)

f) \(\dfrac{49+7.49}{49}=\dfrac{49\left(1+7\right)}{49}=8\)

a. \(\dfrac{8,5-8,2}{16}=\dfrac{0,3}{16}=\dfrac{3}{160}\)

b. \(\dfrac{2\cdot14}{7\cdot8}=\dfrac{1\cdot2}{1\cdot4}=\dfrac{2}{4}=\dfrac{1}{2}\)

c. \(\dfrac{11\cdot4-11}{2-13}=\dfrac{11\left(4-1\right)}{-11}=\dfrac{1\cdot3}{-1}=-3\)

d. \(\dfrac{49+7\cdot49}{49}=\dfrac{49\cdot\left(1+7\right)}{49}=\dfrac{8}{1}=8\)

\(\frac{4\cdot7}{9\cdot32}=\frac{4\cdot7}{9\cdot8\cdot4}=\frac{7}{8\cdot9}=\frac{7}{72}\)

\(\frac{2\cdot5\cdot13}{26\cdot35}=\frac{2\cdot5\cdot13}{2\cdot13\cdot7\cdot5}=\frac{1}{7}\)

\(\frac{3\cdot21}{14\cdot15}=\frac{3\cdot3\cdot7}{2\cdot7\cdot3\cdot5}=\frac{3}{2\cdot5}=\frac{3}{10}\)

\(\frac{9\cdot6-9\cdot3}{18}=\frac{9\cdot\left(6-3\right)}{9\cdot2}=\frac{9\cdot3}{9\cdot2}=\frac{3}{2}\)

\(\frac{17\cdot5-17}{3-20}=\frac{17\cdot\left(5-1\right)}{-17}=\frac{17\cdot4}{17\cdot\left(-1\right)}=\frac{4}{-1}=-4\)

\(45dm^2=0,45m^2\)

\(300cm^2=0,03m^2\)

\(57500mm^2=0,0575m^2\)

a)\(\frac{20}{-160}=-\frac{1}{8}\)

b)\(\frac{-24}{-72}=\frac{1}{3}\)

c)\(-\frac{270}{450}=-\frac{3}{5}\)

d)\(\frac{3.7.11}{33.14}=\frac{33.7}{33.14}=\frac{7}{14}=\frac{1}{2}\)

e)\(\frac{49+7.49}{-49}=\frac{49.\left(1+7\right)}{-49}=\frac{49.8}{-49}=-8\)

\(a,\frac{20}{-160}=\frac{-20:20}{160:20}=\frac{-1}{8}\)

\(b,\frac{-24}{-72}=\frac{-24:24}{-72:24}=\frac{-1}{-3}=\frac{1}{3}\)

\(c,\frac{-270}{450}=\frac{-270:90}{450:90}=\frac{-3}{5}\)

\(d,\frac{3.7.11}{33.14}=\frac{3.7.11}{3.11.7.2}=\frac{1}{2}\)

\(e,\frac{49+7.49}{-49}=-\frac{49.\left(7+1\right)}{49}=-8\)

Học tốt

a) 20/-160 = 1/-8             b) -24/-72 = 1/3              c) -270/450 = -3/5     

d) 3.7.11/33.14 = 3.7.11/3.11.7.2 = 1/2     

 e) 49+7.49/ -49 = 7.7+7.49/-49 = 7.(7+49) /-49 = 7.56/-49 = 392/-49 = -8

a.\(\frac{17.5-17}{-17}=\frac{17.4}{-17}=-4\)

b.\(\frac{49.8}{49}=8\)

a) \(\frac{17.5-17}{3-20}\)= \(\frac{85-17}{3-20}\)= \(\frac{68}{-17}\)=-4

b) \(\frac{49+7.49}{49}\)= \(\frac{49+343}{49}\)= \(\frac{392}{49}\)= 8

CHÚC BẠN HỌC TỐT

a) \(\dfrac{4.7}{9.32}=\dfrac{4.7}{9.4.8}=\dfrac{7}{72}\) b) \(\dfrac{3.21}{14.15}=\dfrac{3.7.3}{7.2.3.5}=\dfrac{3}{10}\)

c) \(\dfrac{2.5.13}{26.35}=\dfrac{2.5.13}{2.13.5.7}=\dfrac{1}{7}\) d)\(\dfrac{9.6-9.3}{18}\) \(=\dfrac{9.\left(6-3\right)}{9.2}=\dfrac{9.3}{9.2}=\dfrac{3}{2}\)

e) \(\dfrac{17.5-17}{3-20}=\dfrac{17.\left(5-1\right)}{-17}=-\dfrac{17.4}{17}=-4\) f) \(\dfrac{49+7.49}{49}=\dfrac{49.\left(1+7\right)}{49}=8\)