Theo đầu bài ta có:
\(\frac{x-7}{7}+\frac{x-7}{8}=\frac{15}{56}\)
\(\Rightarrow\left(x-7\right)\cdot\frac{1}{7}+\left(x-7\right)\cdot\frac{1}{8}=\frac{15}{56}\)
\(\Rightarrow\left(x-7\right)\cdot\left(\frac{1}{7}+\frac{1}{8}\right)=\frac{15}{56}\)
\(\Rightarrow\left(x-7\right)\cdot\frac{15}{56}=\frac{15}{56}\)
\(\Rightarrow x-7=1\)
\(\Rightarrow x=8\)
\(\frac{7}{8}\): ( x + 1 ) = \(\frac{8}{7}\)
Tim x
Tính nhanh
a)\(\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)
b)\(\frac{5}{9}x\frac{1}{2}x\frac{5}{9}x\frac{6}{4}\)
c)\(\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)
d)\(\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)
a)\(\frac{3}{5}-\frac{1}{3}-\frac{1}{6}\)
b)\(\frac{4}{7}x\frac{5}{8}x\frac{7}{12}\)
c)\(\frac{25}{28}:\frac{15}{14}x\frac{6}{7}\)
tính nhanh
\(a,\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)
\(b,\frac{5}{9}x\frac{1}{2}+\frac{5}{9}x\frac{6}{4}\)
\(c,\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)
\(d,\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)
Tính nhanh
a)\(\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)
b)\(\frac{5}{9}x\frac{1}{2}+\frac{5}{9}x\frac{6}{4}\)
c)\(\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)
d)\(\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)
lam ho nha dang can gap
a ) x + 5,84 =9,16
b )\(x=\frac{1}{5}-\frac{3}{7}\)
c)\(\frac{x}{5}=\frac{5}{6}-\frac{13}{30}\)
d )\(x+\frac{3}{4}=\frac{4}{5}\)
e )\(\frac{x}{7}=\frac{7}{8}-\frac{25}{56}\)
a) \(x+\frac{7}{15}=1\frac{1}{20}\)
b) \(\left(3\frac{1}{2}-x\right)\cdot1\frac{1}{4}=\frac{15}{16}\)
c) \(1\frac{1}{5}x+\frac{2}{3}x=\frac{56}{125}\)
d)\(x+2\frac{1}{4}x=\frac{15}{8}\)
e)\(60\%x+0,4x+x:3=2\)
GIÚP MÌNH NHOA CÁC BẠN
Tìm x
\(a,x+\frac{15}{7}=\frac{9}{2}\)
\(b,x-\frac{3}{4}=\frac{7}{2}\)
\(c,x\times\frac{7}{8}=\frac{12}{5}\)
\(d,\frac{5}{6}:x=\frac{4}{3}\)
tìm x biết: \(2009-\left(4\frac{5}{9}+x-7\frac{7}{8}\right):15\frac{3}{2}=2008\)