Question

Tính nhanh :

\(\frac{12}{13}-\frac{2}{7}+\frac{8}{13}+\frac{6}{13}-\frac{5}{7}\)

Answer 1

12/13-2/7-8/13+6/13-5/7=1

Answer 2

\(\frac{12}{13}-\frac{2}{7}+\frac{8}{13}+\frac{6}{13}-\frac{5}{7}\)

\(=\left(\frac{12}{13}+\frac{8}{13}+\frac{6}{13}\right)-\left(\frac{2}{7}+\frac{5}{7}\right)\)

\(=\frac{26}{13}-\frac{7}{7}\)

\(=2-1\)

\(=1\)

Answer 3

\(\frac{12}{13}-\frac{2}{7}+\frac{8}{13}+\frac{6}{13}-\frac{5}{7}\)

\(=\left(\frac{12}{13}+\frac{8}{13}+\frac{6}{13}\right)-\left(\frac{2}{7}+\frac{5}{7}\right)\)

\(=\left(\frac{12+8+6}{13}\right)-\frac{7}{7}\)

\(=\frac{26}{13}-1\)

\(=2-1\)

\(=1\)