Bonjour,
[tex]B = \frac{ \frac{6}{7} }{ \frac{12}{5} } - \frac{1}{7} [/tex]
[tex]B = \frac{6}{7} \times \frac{5}{12} - \frac{1 \times 12}{7 \times 12} [/tex]
[tex]B = \frac{30}{84} - \frac{12}{84} [/tex]
[tex]B = \frac{18}{84} [/tex]
[tex]B = \frac{3 \times 6}{6 \times 14} [/tex]
[tex]B = \frac{3}{14} [/tex]
