Bài 1: Trang 167 - sgk toán lớp 4

Gửi bởi: Nguyễn Thị Ngọc Vào 22 tháng 4 2019 lúc 10:49:55

Tính:

$\frac{2}{7} + \frac{4}{7}$ $\frac{6}{7} - \frac{2}{7}$ $\frac{6}{7} - \frac{4}{7}$ $\frac{4}{7} + \frac{2}{7}$

$\frac{1}{3} + \frac{5}{12}$ $\frac{9}{12} - \frac{1}{3}$ $\frac{9}{12} - \frac{5}{12}$ $\frac{5}{12} + \frac{1}{3}$

$\frac{2}{7} + \frac{4}{7}= \frac{6}{7}$

$\frac{6}{7} - \frac{2}{7}= \frac{5}{7}$

$\frac{6}{7} - \frac{4}{7}= \frac{2}{7}$

$\frac{4}{7} + \frac{2}{7}= \frac{6}{7}$

$\frac{1}{3} + \frac{5}{12}= \frac{4}{12}+ \frac{5}{12}=\frac{9}{12}$

$\frac{9}{12} - \frac{1}{3}= \frac{9}{12} - \frac{4}{12}=\frac{5}{12}$

$\frac{9}{12} - \frac{5}{12}= \frac{4}{12}$

$\frac{5}{12} + \frac{1}{3}= \frac{5}{12}+ \frac{4}{12}=\frac{9}{12}$