Question

3/7X9/26-1/14X1/13=

TINH NHANH

 

Answer 1

\(\frac{3}{7}.\frac{9}{26}-\frac{1}{14}.\frac{1}{13}\)

\(=6.\frac{1}{14}.\frac{1}{13}.\frac{9}{2}-\frac{1}{14}.\frac{1}{13}\)

\(=\frac{1}{14}.\frac{1}{13}.\left(\frac{6.9}{2}-1\right)\)

\(=\frac{1}{182}.26\)

\(=\frac{1}{7}\)

Answer 2

3/7.9/26-1/14.1/13=3.9/7.26-1/14.1/13

                          =27/182-1/14.1/13

                          =27/182-1.1/14.13

                          =27/182-1/182

                          =26/182=1/7