Câu 1: Trang 15 - sgk Toán lớp 5
Tính:
a) $\frac{7}{9}+\frac{9}{10}$
b) $\frac{5}{6}+\frac{7}{8}$
c) $\frac{3}{5}+\frac{1}{2}+\frac{3}{10}$
Bài Làm:
a. $\frac{7}{9}+\frac{9}{10}=\frac{70 + 81}{10}=\frac{151}{10}$
b. $\frac{5}{6}+\frac{7}{8}=\frac{20 + 21}{24}=\frac{41}{24}$
c. $\frac{3}{5}+\frac{1}{2}+\frac{3}{10}=\frac{6+5+3}{10}=\frac{14}{10}=\frac{7}{5}$