rút gọn các phân số sau:
a) \(\dfrac{22}{55}=\) b) \(\dfrac{-63}{81}=\)
c)\(\dfrac{2.14}{7.8}=\) d)\(\dfrac{49+7.49}{49}=\)
rút gọn các phân số sau:
a,\(\dfrac{8.5-8.2}{16}\)
b,\(\dfrac{2.14}{7.8}\)
c\(\dfrac{11.4-11}{2-13}\)
d,\(\dfrac{17.5-17}{3-20}\)
e,\(\dfrac{49+7.49}{49}\)
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. \(\dfrac{49+7\cdot49}{49}=\dfrac{49\cdot\left(1+7\right)}{49}=\dfrac{8}{1}=8\)
Rút gọn các phân số sau :
a) \(\dfrac{22}{55}\)
b) \(-\dfrac{63}{81}\)
c) \(\dfrac{20}{-140}\)
d) \(\dfrac{-25}{-75}\)
a) Số?
\(\dfrac{56}{42}=\dfrac{28}{?}=\dfrac{?}{3}\) \(\dfrac{16}{24}=\dfrac{2}{?}=\dfrac{?}{12}=\dfrac{40}{?}\)
b) Rút gọn các phân số: \(\dfrac{40}{25};\dfrac{63}{81};\dfrac{36}{60}\)
a) \(\dfrac{56}{42}=\dfrac{28}{21}=\dfrac{4}{3}\)
\(\dfrac{16}{24}=\dfrac{2}{3}=\dfrac{8}{12}=\dfrac{40}{60}\)
b) \(\dfrac{40}{25}=\dfrac{8}{5}\)
\(\dfrac{63}{81}=\dfrac{7}{9}\)
\(\dfrac{36}{60}=\dfrac{3}{5}\)
Viết phân số rút gọn của các phân số sau:
a, \(\dfrac{30}{84}\)=........ b,\(\dfrac{35}{210}\)=...........
c,\(\dfrac{210}{140}\)=........ d,\(\dfrac{320}{280}\)=...........
Rút gọn :
a) \(\dfrac{3.5}{8.24}\)
b) \(\dfrac{2.14}{7.8}\)
c) \(\dfrac{3.7.11}{22.9}\)
d) \(\dfrac{8.5-8.2}{16}\)
e) \(\dfrac{11.4-11}{2-13}\)
Rút gọn các phân số sau:
a)\(\dfrac{11.8-11.3}{17-6}\) ; b)\(\dfrac{24-12.13}{12+4.9}\); c)\(\dfrac{7.6-7.4}{7.3}\); d)\(\dfrac{7}{9.10^2-2.10^2}\)
a) \(\dfrac{11\cdot8-11\cdot3}{17-6}\)
\(=\dfrac{11\cdot\left(8-3\right)}{11}=5\)
b) \(\dfrac{24-12\cdot13}{12+4\cdot9}\)
\(=\dfrac{12\cdot\left(2-13\right)}{12\left(1+3\right)}=\dfrac{-11}{4}\)
Rút gọn các phân số sau:
a)\(\dfrac{13.9-13.2}{25-12}\) b) \(\dfrac{42-14.8}{7+21.3}\)
c)\(\dfrac{9.6-18.4}{12.3}\)
d)\(\dfrac{5.5^2}{9.10^2-4.10^2}\)
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: \(=\dfrac{5^3}{10^2\cdot5}=\dfrac{5^2}{100}=\dfrac{1}{4}\)
Bài 1: Rút gọn rồi tính
a) \(\dfrac{22}{55}+\dfrac{25}{125}+\dfrac{1020}{5100}\)
b) \(\dfrac{22}{77}+\dfrac{56}{98}+\dfrac{25}{105}\)
(Các bạn giải chi tiết cho mình ạ!)
= 2/5 + 1/5 + 1/5
= 4/5
b. = 2/7 + 4/7 + 5/21
= 6/21 + 12/21 + 5/21
= 23/21
HT
Rút gọn các phân số sau: a) \(\dfrac{-21}{28}\); \(\dfrac{-39}{52}\); \(\dfrac{-24}{63}\); \(\dfrac{12}{-21}\) b, \(\dfrac{-270}{450}\); \(\dfrac{11}{-143}\); \(\dfrac{-132}{156}\); \(\dfrac{-26}{169}\)