4/8 + 8/24 = 1/2+1/3 = 5/6

8/28 + 5/30 = 2/7 +1/6 = 19/42

k cho mik nha !

Rút gọn:

\(\frac{18}{30}=\frac{18:6}{30:6}=\frac{3}{5}\)

\(\frac{36}{27}=\frac{36:9}{27:9}=\frac{4}{3}\)

\(\frac{64}{80}=\frac{64:16}{80:16}=\frac{4}{5}\)

\(\frac{45}{35}=\frac{45:5}{35:5}=\frac{9}{7}\)

bài dễ tự làm đi 

a) \(\frac{8}{5}-\frac{18}{27}=\frac{8}{5}-\frac{2}{3}\)

\(\Rightarrow\frac{8}{5}-\frac{2}{3}=\frac{24}{15}-\frac{10}{15}\)

\(\Rightarrow\frac{14}{15}\)

b) \(\frac{18}{21}-\frac{12}{27}=\frac{6}{7}-\frac{4}{9}\)

\(\Rightarrow\frac{6}{7}-\frac{4}{9}=\frac{54}{63}-\frac{28}{63}\)

\(\Rightarrow\frac{26}{63}\)

c) \(\frac{8}{24}-\frac{5}{25}=\frac{1}{3}-\frac{1}{5}\)

\(\Rightarrow\frac{1}{3}-\frac{1}{5}=\frac{5}{15}-\frac{3}{15}\)

\(\Rightarrow\frac{2}{15}\)

d) \(\frac{12}{20}-\frac{6}{18}=\frac{3}{5}-\frac{1}{3}\)

\(\Rightarrow\frac{3}{5}-\frac{1}{3}=\frac{9}{15}-\frac{5}{15}\)

\(\Rightarrow\frac{4}{15}\)

https://olm.vn/hoi-dap/question/1037641.html

Rút gọn các phân số sau :

\(\frac{18}{30}=\frac{18\div6}{30\div6}=\frac{3}{5}\)

\(\frac{64}{80}=\frac{64\div16}{80\div16}=\frac{4}{5}\)

\(\frac{36}{27}=\frac{36\div9}{27\div9}=\frac{4}{3}\)

\(\frac{45}{35}=\frac{45\div5}{35\div5}=\frac{9}{7}\)

a)2/5+3/5 = 1

b)7/8+5/8 = 12/8= 3/2

c) 1/2+1/3 = 5/6

d) 2/7+1/6= 19/42

a, 2/5 + 9/15          28/32 + 45/72               b, 4/8 + 8/24                 8/28 + 5/30

= 2/5 + 3/5            = 7/8 + 5/8                     = 1/2 + 1/3                   = 2/7 + 1/6

= 1.                        = 3/2.                              = 5/6.                            = 19/42.

k cho mik nha !

Rút gọn các phân số ta được:

\(\frac{42}{63}=\frac{2}{3}\);\(\frac{5}{9}=\frac{5}{9}\);\(\frac{14}{18}=\frac{7}{9}\);\(\frac{27}{81}=\frac{1}{3}\);\(\frac{10}{10}=1\)

Viết các phân số trên theo thứ tự tăng dần:

Ta thấy: \(\frac{1}{3}< \frac{5}{9}< \frac{2}{3}< \frac{7}{9}< 1\)

\(\Rightarrow\frac{27}{81}< \frac{5}{9}< \frac{42}{63}< \frac{14}{18}< \frac{10}{10}\)

\(\frac{8}{5}-\frac{18}{27}\)

\(=\frac{8}{5}-\frac{2}{3}\)

\(=\frac{24}{15}-\frac{10}{15}\)

\(=\frac{14}{15}\)

\(\frac{12}{20}-\frac{6}{18}\)

\(=\frac{3}{5}-\frac{1}{3}\)

\(=\frac{9}{15}-\frac{5}{15}\)

\(=\frac{4}{15}\)

\(\frac{8}{24}-\frac{5}{25}\)

\(=\frac{1}{3}-\frac{1}{5}\)

\(=\frac{5}{15}-\frac{3}{15}\)

\(=\frac{2}{15}\)

\(\frac{18}{21}-\frac{12}{27}\)

\(=\frac{6}{7}-\frac{4}{9}\)

\(=\frac{54}{63}-\frac{28}{63}\)

\(=\frac{26}{63}\)

1)8/5-2/3=14/15

2)3/5-1/3=4/15

3)1/3-1/5=2/15

4)6/7-4/9=26/63

mình vừa làm cho bạn rồi thây

câu 1: 0

\(\frac{24}{36}\)