Question

[nguyễn thị oanh]

Tìm số chưa biết

\(\frac{1}{2}a-\frac{3}{4}=\frac{5}{15}\)

\(1\frac{8}{15}-\frac{2}{3}=0.2\)

\(\left(x+\frac{1}{8}\right):\frac{2}{3}=3-\frac{3}{4}\)

các bạn làm đc câu nào làm nha

mik sẽ like hết cho

Answer 1

[Kiệt Nguyễn]

\(\frac{1}{2}a-\frac{3}{4}=\frac{5}{15}\)

\(\Leftrightarrow\frac{1}{2}a-\frac{3}{4}=\frac{1}{3}\)

\(\Leftrightarrow\frac{1}{2}a=\frac{1}{3}+\frac{3}{4}\)

\(\Leftrightarrow\frac{1}{2}a=\frac{4}{12}+\frac{9}{12}\)

\(\Leftrightarrow\frac{1}{2}a=\frac{13}{12}\)

\(\Leftrightarrow a=\frac{13}{12}\div\frac{1}{2}\)

\(\Leftrightarrow a=\frac{13}{12}\times\frac{2}{1}\)

\(\Leftrightarrow a=\frac{13}{6}\)

Answer 2

[‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍...]

\(\left(x+\frac{1}{8}\right):\frac{2}{3}=3-\frac{3}{4}\)

\(\left(x+\frac{1}{8}\right):\frac{2}{3}=\frac{9}{4}\)

\(x+\frac{1}{8}=\frac{9}{4}.\frac{2}{3}\)

\(x+\frac{1}{8}=\frac{3}{2}\)

\(x=\frac{3}{2}-\frac{1}{8}\)

\(x=\frac{11}{8}\)

Vậy \(x=\frac{11}{8}\)