a.\(\frac{15}{8}=\frac{45}{24}\) b.\(\frac{8}{11}=\frac{224}{308}\)
\(\frac{7}{21}=\frac{1}{3}=\frac{8}{24}\) \(\frac{9}{7}=\frac{396}{308}\)
\(\frac{19}{6}=\frac{76}{24}\) \(\frac{5}{4}=\frac{385}{308}\)
15/8=15*21*16/8*21*16=................./.......................... những phép còn lại cũng thế!