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\(x+\frac{4}{5}=\frac{45}{5}-\left(\frac{3}{7}+\frac{3}{5}\right)\)
\(x+\frac{4}{5}=9-\frac{36}{35}\)
\(x+\frac{4}{5}=\frac{279}{35}\)
\(\Rightarrow x=\frac{251}{35}\)
\(x+\frac{4}{5}=\frac{45}{5}-\left(\frac{3}{7}+\frac{3}{5}\right)\)
\(\Leftrightarrow x+\frac{4}{5}=9-\left(\frac{3}{7}+\frac{3}{5}\right)\)
\(\Leftrightarrow x+\frac{4}{5}=9-\frac{3}{7}-\frac{3}{5}\)
\(\Leftrightarrow x+\frac{4}{5}=\frac{315}{35}-\frac{15}{35}-\frac{21}{35}\)
\(\Leftrightarrow x+\frac{4}{5}=\frac{279}{35}\)
\(\Leftrightarrow x=\frac{279}{35}-\frac{4}{5}\)
\(\Leftrightarrow x=\frac{251}{35}\)
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x+2/5=1/2
x. =1/2-2/5
x. =3/10
d)2/3-x=8/21
x=2/3-8/21
x=8/21. ( cho mik đi bạn)
a) 1/3+1/6+4/3+2/3+5/6
= 2/6+1/6+8/6+4/6+5/6
= 20/6=10/3
b)5/7+x/35=4/5
x/35=4/5-5/7
x/35=8/35
=> x. =8 ( cho mik đi rồi mik lm tiếp cho)
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Tìm x :
x + 1/3 = 4/5
x = 4/5 - 1/3
x = 12/15 - 5/15
x = 7/15
x - 1/2 = 2/7
x = 2/7 + 1/2
x = 4/14 + 7/14
x = 11/14
4/7 × x = 1/3
x = 1/3 : 4/7
x = 1/3 × 7/4
x = 7/12
x : 2/5 = 2/9
x = 2/9 × 2/5
x = 4/45
20 × 7 : ( 5 × x - 3 × 5 ) = 4
140 : 5 × ( x - 3 ) = 4
5 × ( x - 3 ) = 140 : 4
5 × ( x - 3 ) = 35
x - 3 = 35 : 5
x - 3 = 7
x = 7 + 3
x = 10
x - 270 = 420 : 105
x - 270 = 4
x = 4 + 270
x = 274
x - 140 : 35 = 270
x - 4 = 270
x = 270 + 4
x = 274
x + 1/3 = 4/5
x = 4/5 - 1/3
x = 7/15
x - 1/2 = 2/7
x = 2/7 + 1/2
x = 11/14
4/7 * x = 1/3
x = 1/3 : 4/7
x = 7/12
x : 2/5 = 2/9
x = 2/9 * 2/5
x 4 / 45
20 * 7 : ( 5*x - 3 * 5) =4
= 140 :(5*x -3 *5) =4
5*x- 3*5 = 140 : 4
5*x - 3 * 5 = 35
5* x = 35 + 3 * 5
5 * x = 50
x = 50 : 5
x = 10
x - 270 = 402 : 105
x - 270 = 4
x = 270 + 4
x = 274
x- 140 : 35 = 270
x - 4 = 270
x = 270 + 4
x = 274
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\(1)\frac{12}{7}\times \frac{7}{4}+\frac{35}{11}:\frac{245}{121}\)
\(=3+\frac{35}{11}\times \frac{121}{245}\)
\(=3+\frac{11}{7}\)
\(= 3\frac{1}{7}(=\frac{22}{7})\)
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\(3+\frac{35}{21}+6=\frac{3}{1}+\frac{35}{21}+\frac{6}{1}=\frac{63}{21}+\frac{35}{21}+\frac{126}{21}=\frac{224}{21}\)
\(\frac{3}{8}+\frac{1}{5}+7=\frac{3}{8}+\frac{1}{5}+\frac{7}{1}=\frac{15}{40}+\frac{8}{40}+\frac{280}{40}=\frac{303}{40}\)
\(\frac{14}{28}+\frac{3}{4}+2=\frac{2}{4}+\frac{3}{4}+2=\frac{2}{4}+\frac{3}{4}+\frac{2}{1}=\frac{2}{4}+\frac{3}{4}+\frac{8}{4}=\frac{13}{4}\)
\(\frac{3}{5}+\frac{1}{4}+\frac{2}{3}=\frac{36}{60}+\frac{15}{60}+\frac{40}{60}=\frac{91}{60}\)
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a) 2/5+9/5=11/5
b) 15/45+25/30=7/6
c) 28/32+45/72=3/2
d) 8/28+5/30=19/42
bài 2
a) x - 4/5 =4/5 + (3/7+3/5)
x-4/5=4/5+36/35
x-4/5=64/35
x=64/35+4/5
x=92/35
b) x-7/35=4/5
x=4/5+7/35
x=1
nhớ tk m nhé
a = 18/5
b = 3/9 + 5/6 = 6/18 + 25/18 = 31/18
c = 7/8 + 5/8 = 12/8
d = 4/14 + 1/6 = 14/42 + 7/42 = 21/42 -= 7/14
b2
x - 4/5 = 4.5 + ( 3/7 + 3/5 )
x - 4/5 = 49/35
x = 49/35 + 4/5
x = 77/35
x - 7/35 = 4/5
x = 4/5 + 7/35
x = 1
mình ko chắc chắn đâu
mình nghĩ mình làm sai
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2/7 + 3/5
= 10/35 + 21/35
= 31/35
31/35 - 2/7
= 31/35 - 10/35
= 21/35
= 3/5
31/35 - 2/5
= 31/35 - 14/35
= 17/35
3/5 + 2/7
= 21/35 + 10/35
= 31/35
2/7 + 3/5 = 10/35 + 21/35 = 31/35
31/35 - 2/7 = 31/35 - 10/35 = 21/35
31/35 - 2/5 = 31/35 - 21/35 = 10/35
3/5 + 2/7 = 21/35 + 10/35 = 31/35
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\(\frac{6-2}{5}+\frac{3}{5.3}\)
\(=\frac{4}{5}+\frac{1}{5.1}\)
\(=\frac{4}{5}+\frac{1}{5}\)
\(=\frac{5}{5}=1\)
a. 6 x 3 - ( \(\frac{2}{5}+\frac{3}{5}\)) = 6 x 3 - \(\frac{5}{5}\)= 6 x 3 - 1 = 18 - 1 = 17
b.( \(\frac{31}{35}-\frac{4}{7}\)) x \(\frac{8}{7}\): 2 =\(\frac{11}{35}\)x \(\frac{8}{7}\): 2 =\(\frac{88}{245}\): 2 = \(\frac{88}{490}\)= \(\frac{44}{245}\)= ...........rút gọn đến khi hết
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a) \(6-\frac{2}{5}+\frac{3}{5}\times3\)
\(=6-\frac{2}{5}+\frac{9}{5}\)
\(=\frac{30}{5}-\frac{2}{5}+\frac{9}{5}\)
\(=\frac{28}{5}+\frac{9}{5}\)
\(=\frac{37}{5}\)
b) \(\left(\frac{31}{35}-\frac{4}{7}\right)\times\frac{8}{7}:2\)
\(=\frac{11}{35}\times\frac{8}{7}:2\)
\(=\frac{88}{245}:2\)
\(=\frac{44}{245}\)
\(\frac{3}{5}+\frac{4}{5}+\frac{5}{7}-\frac{3}{35}\)
\(=\frac{21}{35}+\frac{28}{35}+\frac{25}{35}-\frac{3}{35}\)
\(=\frac{21+28+25-3}{35}\)
\(=\frac{21+\left(28-3\right)+25}{35}\)
\(=\frac{21+25+25}{35}\)
\(=\frac{21+\left(25+25\right)}{35}\)
\(=\frac{21+50}{35}\)
\(=\frac{71}{35}\)
\(\frac{3}{5}+\frac{4}{5}+\frac{5}{7}-\frac{3}{35}\)
\(=\frac{21}{35}+\frac{28}{35}+\frac{25}{35}-\frac{3}{35}\)
\(=\frac{21+28+25-3}{35}\)
\(=\frac{71}{35}\)
HỌC TỐT NHÉ !