Bài 1: \(\frac{5}{12}-\frac{5}{18}\)
\(=\frac{5.3}{12.3}-\frac{5.2}{18.2}\)
\(=\frac{15}{36}-\frac{10}{36}\)
\(=\frac{5}{36}.\)
\(\frac{17}{15}-\frac{5}{9}-\frac{2}{11}\)
\(=\frac{17.33}{15.33}-\frac{5.55}{9.55}-\frac{2.45}{11.45}\)
\(=\frac{561}{495}-\frac{275}{495}-\frac{90}{495}\)
\(=\frac{196}{495}.\)
90/219 - 60/219=30/219=10/37