a) \(\frac{5}{7}\)và \(\frac{7}{9}\)
Ta có :
\(\frac{5}{7}=\frac{5\times9}{7\times9}=\frac{45}{63}\)
\(\frac{7}{9}=\frac{7\times7}{9\times7}=\frac{49}{63}\)
Vì \(45< 49\)nên \(\frac{45}{63}< \frac{49}{63}\)hay \(\frac{5}{7}< \frac{7}{9}\)
b) \(\frac{16}{35}\)và \(\frac{4}{7}\)
\(\frac{16}{35}=\frac{16}{35}\)
\(\frac{4}{7}=\frac{4\times5}{7\times5}=\frac{20}{35}\)
Vì \(16< 20\)nên \(\frac{16}{35}< \frac{20}{35}\)hay \(\frac{16}{35}< \frac{4}{7}\)
c) \(\frac{13}{15}\)và \(\frac{11}{12}\)
\(\frac{13}{15}=\frac{13\times4}{15\times4}=\frac{52}{60}\)
\(\frac{11}{12}=\frac{11\times5}{12\times5}=\frac{55}{60}\)
Vì \(52< 55\)nên \(\frac{52}{60}< \frac{55}{60}\)hay \(\frac{13}{15}< \frac{11}{12}\)
a.\(\frac{5}{7}< \frac{7}{9}\)
b.\(\frac{16}{35}< \frac{4}{7}\)
c.\(\frac{13}{15}< \frac{11}{12}\)
a. 5/7 < 7/9 b. 16 / 35 < 4/7
c. 13/15 < 11/12 ******************
Học giỏi #