\(\frac{2}{7}+\frac{5}{7}=\frac{7}{7}=1\)
\(\frac{8}{15}+\frac{6}{15}=\frac{14}{15}\)
\(\frac{2}{3}+\frac{3}{9}+\frac{4}{9}=\frac{6}{9}+\frac{3}{9}+\frac{4}{9}=\frac{9}{9}+\frac{4}{9}=\frac{13}{9}\)
2/7 + 5/7 = 7/7 = 1
8/15 + 6/15 = 14/15
2/3 + 3/9 + 4/9 = 6/9 + 3/9 + 4/9 = 13/9
1.\(\frac{2}{7}+\frac{5}{7}=\frac{2+5}{7}=\frac{7}{7}\)
2.\(\frac{8}{15}+\frac{6}{15}=\frac{8+6}{15}=\frac{14}{15}\)
Mk chỉ làm đc 2 câu đầu thôi
