Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
3/4 và 5/18,4/9
3/4=3 x 9 =27;4 x 9=36 27/36
4/9=4 x4 =16/36,9 x 4 =36 16/36
5/18 là đúng
5/18=5x2=10;18 x2=36 10/36
a) \(\left(8\frac{4}{5}x-50\right):0,4=5\)
\(\Rightarrow\left(\frac{44}{5}x-50\right)=5.0,4\)
\(\Rightarrow\frac{44}{5}x-50=2\)
\(\Rightarrow\frac{44}{5}x=2+50\)
\(\Rightarrow\frac{44}{5}x=52\)
\(\Rightarrow x=\frac{65}{11}\)
b) \(\left(\frac{5x}{3}-3\right):15=\frac{3}{10}\)
\(\Rightarrow\frac{5x}{3}-3=\frac{3}{10}.15\)
\(\Rightarrow\frac{5x}{3}-3=\frac{45}{10}\)
\(\Rightarrow\frac{5x}{3}=\frac{45}{10}+3\)
\(\Rightarrow\frac{5x}{3}=\frac{15}{2}\)
\(\Rightarrow5x.2=3.15\)
=> 5x.2 = 45
=> 5x = 45 : 2
=> 5x = 45/2
=> x = 9/2
a) 2 và 4/5 = 14/5 ; 1 và 3/10 = 13/10
14/5 + 13/10 = 41/10
b) 1 và 2/7 = 9/7
9/7 + 5/9 = 116/63
Khi nào rảnh vào kênh H-EDITOR xem vid nha!!! Thanks!
Bài giải
\(\frac{2}{3}+\frac{3}{4}+\frac{4}{5}=\frac{40}{60}+\frac{45}{60}+\frac{48}{60}=\frac{133}{60}\)
\(\frac{8}{5}+\frac{7}{6}+\frac{10}{9}+\frac{1}{2}=\frac{144}{90}+\frac{105}{90}+\frac{100}{90}+\frac{45}{90}=\frac{394}{90}\)
\(\frac{15}{17}-\frac{11}{13}+\frac{3}{26}=\frac{390}{442}+\frac{374}{442}+\frac{51}{442}=\frac{815}{442}\)
\(\frac{9}{12}\text{ x }\frac{4}{3}\text{ : }\frac{8}{5}=\frac{9}{12}\text{ x }\frac{4}{3}\text{ x }\frac{5}{8}=\frac{9\text{ x }4\text{ x }5}{12\text{ x }3\text{ x }8}=\frac{5}{8}\)
\(\frac{4}{5}\text{ x }\frac{15}{8}\text{ : }\frac{5}{7}=\frac{4}{5}\text{ x }\frac{15}{8}\text{ x }\frac{7}{5}=\frac{4\text{ x }15\text{ x }7}{5\text{ x }8\text{ x }5}=\frac{21}{10}\)
\(\frac{2}{3}+\frac{3}{4}+\frac{4}{5}=\frac{40}{60}+\frac{45}{60}+\frac{48}{60}=\frac{133}{60}\)
\(\frac{8}{5}+\frac{7}{6}+\frac{10}{9}+\frac{1}{2}=\frac{144}{90}+\frac{105}{90}+\frac{100}{90}+\frac{45}{90}=\frac{197}{45}\)
\(\frac{15}{17}-\frac{11}{13}+\frac{1}{26}=\frac{390}{442}+\frac{374}{442}+\frac{51}{442}=\frac{815}{442}\)
\(\frac{9}{12}\times\frac{4}{3}:\frac{8}{5}=1:\frac{8}{5}=\frac{5}{8}\)
\(\frac{4}{5}\times\frac{15}{8}:\frac{5}{7}=\frac{3}{2}:\frac{5}{7}=\frac{21}{10}\)
đề = \(\frac{2}{2.3}+\frac{2}{3.4}+...+\frac{2}{50.51}\)( áp dụng c.thức tính tổng )
= ..........
= 2 .( \(\frac{1}{2}-\frac{1}{51}\))
= dễ
a) x-5/7=3/5x1/2
x-5/7=3/10
x. =3/10+5/7
x. =71/70
b) Xx2/3=5/8x3/4
Xx2/3=15/32
X =15/32:2/3
X =45/64
a) x - 5/7 = 3/5 × 1/2
x - 5/7 = 3/10
x = 3/10 + 5/7
x = 71/70
b) x × 2/3 = 5/8 × 3/4
x × 2/3 = 15/32
x = 15/32 : 2/3
x = 45/64
\(2\dfrac{1}{10}-\dfrac{3}{4}-\dfrac{2}{5}\)
\(=\dfrac{21}{10}-\dfrac{3}{4}-\dfrac{2}{5}\)
\(=\dfrac{42}{20}-\dfrac{15}{20}-\dfrac{8}{20}\)
\(=\dfrac{19}{20}\)