Bài tập 1 trang 54 vbt Toán 4 tập 2 Cánh diều
Tính:
$\frac{1}{3}+\frac{2}{9}$
$\frac{1}{2}+\frac{3}{8}$
$\frac{5}{12}+\frac{2}{3}$
$\frac{5}{16}+\frac{3}{8}$
$\frac{4}{15}+\frac{3}{5}$
$\frac{8}{63}+\frac{10}{7}$
Bài Làm:
$\frac{1}{3}+\frac{2}{9}=\frac{3}{9}+\frac{2}{9}=\frac{3+2}{9}=\frac{5}{9}$
$\frac{1}{2}+\frac{3}{8}=\frac{4}{8}+\frac{3}{8}=\frac{4+3}{8}=\frac{7}{8}$
$\frac{5}{12}+\frac{2}{3}=\frac{5}{12}+\frac{8}{12}=\frac{5+8}{12}=\frac{13}{12}$
$\frac{5}{16}+\frac{3}{8}=\frac{5}{16}+\frac{6}{16}=\frac{5+6}{16}=\frac{11}{16}$
$\frac{4}{15}+\frac{3}{5}=\frac{4}{15}+\frac{9}{15}=\frac{4+9}{15}=\frac{13}{15}$
$\frac{8}{63}+\frac{10}{7}=\frac{8}{63}+\frac{90}{63}=\frac{8+90}{63}=\frac{98}{63}=\frac{98:7}{63:7}=\frac{14}{9}$