Bonjour,
[tex]A = \frac{1}{6} + \frac{3}{4} - \frac{7}{24} [/tex]
[tex]A = \frac{1 \times 4}{6 \times 4} + \frac{6 \times 3}{6 \times 4} - \frac{7}{24} [/tex]
[tex]A = \frac{4}{24} + \frac{18}{24} - \frac{7}{24} [/tex]
[tex]A = \frac{4 + 18 - 7}{24} [/tex]
[tex]A = \frac{15}{24} = \frac{3 \times 5}{3 \times 8} = \frac{5}{8} [/tex]
[tex]B = \frac{2}{3} - \frac{7}{18} + \frac{2}{9} [/tex]
[tex]B = \frac{2 \times 6}{3 \times 6} - \frac{7}{18} + \frac{2 \times 2}{2 \times 9} [/tex]
[tex]B = \frac{12}{18} - \frac{7}{18} + \frac{4}{18} [/tex]
[tex]B = \frac{12 - 7 + 4}{18} [/tex]
[tex]B = \frac{9}{18} = \frac{9 \times 1}{9 \times 2} = \frac{1}{2} [/tex]
