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\(\dfrac{8}{9}+\dfrac{3}{18}=\dfrac{16}{18}+\dfrac{3}{18}=\dfrac{19}{18}\) \(\dfrac{5}{7}-\dfrac{4}{11}=\dfrac{55}{77}-\dfrac{28}{77}=\dfrac{3}{11}\)
\(\dfrac{3}{4}+\dfrac{4}{5}=\dfrac{15}{20}+\dfrac{16}{20}=\dfrac{21}{20}\) \(\dfrac{5}{7}-\dfrac{3}{5}=\dfrac{25}{35}-\dfrac{21}{35}=\dfrac{4}{35}\)
\(\dfrac{7}{9}X\dfrac{3}{4}=\dfrac{7}{9}X\dfrac{3}{4}=\dfrac{7}{12}\) \(\dfrac{8}{3}X\dfrac{21}{4}=\dfrac{8}{3}X\dfrac{21}{4}=14\)
\(\dfrac{12}{7}:\dfrac{1}{4}=\dfrac{12}{7}X\dfrac{4}{1}=\dfrac{48}{7}\) \(\dfrac{7}{2}:\dfrac{9}{4}=\dfrac{7}{2}X\dfrac{4}{9}=\dfrac{14}{9}\)
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a) 4 + 5/7 = .... 28/7 + 5/7=.33/7..............
5/9 x 6/7 = ..10/21....
3 - 7/5 = 15/5 - 7/5...8/5........
3/5 x 4/8 = ..3/10....
b) 2 - 1/4 = .8/4 - 1/4...7/4...
4 : 5/9 = ..4 x 9/5 = 36/5....
2/9 x 3/5 = .....2/15.....
3/8 : 4 = ......3/8 x 1/4 = 3/2.....
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1)2/6=14/42 2)5/9=25/45
4/7=24/42 6/5=54/45
3)7/2=28/8 4)4/9=28/63
5/8 =5/8 8/7=72/63
CÁC Ý CÒN LẠI BẠN LÀM NỐT NHÉ
2/6 và 4/7
Mẫu số chung:42
\(\frac{2}{6}=\frac{2\times7}{6\times7}=\frac{14}{42}\);\(\frac{4}{7}=\frac{4\times6}{7\times6}=\frac{24}{42}\)
5/9 và 6/5
Mẫu số chung: 45
\(\frac{5}{9}=\frac{5\times5}{9\times5}=\frac{25}{45}\); \(\frac{6}{5}=\frac{6\times9}{5\times9}=\frac{54}{45}\)
7/2 và 5/8
Mẫu số chung:8
\(\frac{7}{2}=\frac{7\times4}{2\times4}=\frac{28}{8}\);\(\frac{5}{8}\)
4/9 và 8/7
Mẫu số chung: 63
\(\frac{4}{9}=\frac{4\times7}{9\times7}=\frac{28}{63};\frac{8}{7}=\frac{8\times9}{7\times9}=\frac{72}{63}\)
9/4 và 2/6
Mẫu số chung:12
\(\frac{9}{4}=\frac{9\times3}{4\times4}=\frac{27}{12};\frac{2}{6}=\frac{2\times2}{6\times2}=\frac{4}{12}\)
4/3 và 9/4
Mẫu số chung:12
\(\frac{4}{3}=\frac{4\times4}{3\times4}=\frac{16}{12}\);\(\frac{9}{4}=\frac{9\times3}{4\times3}=\frac{27}{12}\)
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= 51/20
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= 3/14
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= 4/7 - 2/7
= 2/7
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= 17/45
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= 2/3
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= 2 x 1/4
= 1/2
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8/9 x 5/4 + 3/5 = 10/9 + 3/5 = 77/45
5/8 + 1/4 = 5/9 + 2/8 = 7/8
1/2 + 5/9 = 9/18 + 5/9 = 14/9
9/8 x 3/4 - 4/7 = 27/32 - 4/7 = 61/224
a) \(\dfrac{8}{9}:\dfrac{4}{5}+\dfrac{3}{5}=\dfrac{8}{9}\times\dfrac{5}{4}+\dfrac{2}{5}=\dfrac{10}{9}+\dfrac{2}{5}=\dfrac{50}{45}+\dfrac{18}{45}=\dfrac{68}{45}\)
b) \(\dfrac{5}{8}+\dfrac{1}{4}=\dfrac{5}{8}+\dfrac{2}{8}=\dfrac{6}{8}=\dfrac{3}{4}\)
c) \(\dfrac{7}{8}\times\dfrac{4}{7}+\dfrac{5}{9}=\dfrac{1}{2}+\dfrac{5}{9}=\dfrac{9}{18}+\dfrac{10}{18}=\dfrac{19}{18}\)
d) \(\dfrac{9}{8}:\dfrac{4}{3}-\dfrac{4}{7}=\dfrac{9}{8}\times\dfrac{3}{4}-\dfrac{4}{7}=\dfrac{27}{32}-\dfrac{4}{7}=\dfrac{61}{244}\)
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1+2+3+4+5+6+7+8+9+1+2+3+4+5+6+7+8+9+1+2+3+4+5+6+7+8+9=135
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\(\dfrac{3}{4}\) = \(\dfrac{3.5}{4.5}\) = \(\dfrac{15}{20}\); \(\dfrac{4}{5}=\dfrac{4.4}{5.4}\) = \(\dfrac{16}{20}\)
\(\dfrac{4}{7}\) = \(\dfrac{4.9}{7.9}\) = \(\dfrac{36}{63}\); \(\dfrac{5}{9}\) = \(\dfrac{5.7}{9.7}\) = \(\dfrac{35}{63}\)
\(\dfrac{5}{12}\) = \(\dfrac{5.3}{12.3}\) = \(\dfrac{15}{36}\); \(\dfrac{4}{9}=\dfrac{4.4}{9.4}\) = \(\dfrac{16}{36}\)
\(\dfrac{7}{9}=\dfrac{7.8}{9.8}\) = \(\dfrac{56}{72}\) ; \(\dfrac{5}{8}\) = \(\dfrac{5.9}{8.9}\) = \(\dfrac{45}{72}\)
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3/7 + 4 = 3/7 + 4/1 = 31/7
5/9 x 3 =5/9 x 3/1 = 15/9 = 5/3
7/8 - 2/9 =7/8 - 2/9 =47/72
5 - 3/4 =5/1 - 3/4 = 20/4 - 3/4 = 17/4
5/7 : 6 = 5/7 : 6/1 = 5/7 x 1/6 = 5/42
5/6 x 2/7 =10/42= 5/21
3 + 3/4 = 3/1 + 3/4 = 12/4+ 3/4 =15/4
3/5 x 4/8 =12/40 = 3/10.
5 : 3/8 = 5/1 : 3/8 = 5/1 x 8/5 = 8/1= 8
3 x 5/9 =3/1 x 5/9 = 15/9=5/3
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Tính:
2/7 + 5/7=1
8/15 + 6/15 =14/15
2/9 + 3/9 + 4/9=9/9=1
[ Không cần làm phép tính ]Điền vào ô trống <,>,= :
3/5 + 1/5 = 1/5 + 3/5
7/9 + 1/9 < 7/9 + 1/9 + 1/9
3/7 + 2/7 < 3/7 + 4/7
1/5 + 3/5 < 2/5 + 3/5
Tính:
2/7 + 5/7=1
8/15 + 6/15 =14/15
2/9 + 3/9 + 4/9=9/9=1
[ Không cần làm phép tính ]Điền vào ô trống <,>,= :
3/5 + 1/5 = 1/5 + 3/5
7/9 + 1/9 < 7/9 + 1/9 + 1/9
3/7 + 2/7 < 3/7 + 4/7
1/5 + 3/5 < 2/5 + 3/5
\(\dfrac{5}{4}\): 4 + \(\dfrac{7}{9}\)
= \(\dfrac{5}{4}\) \(\times\) \(\dfrac{1}{4}\) + \(\dfrac{7}{9}\)
= \(\dfrac{5}{16}\) + \(\dfrac{7}{9}\)
= \(\dfrac{45}{144}\) + \(\dfrac{112}{144}\)
= \(\dfrac{157}{144}\)