Question

2/7×(3/4-7/8)+9/15×7/8-3/5​

Answer 1

$\frac{2}{7} \times ( \frac{3}{4} - \frac{7}{8} ) + \frac{9}{15} \times \frac{7}{8} - \frac{3}{8} \\ = \frac{2}{7}( \frac{6 - 7}{8} ) + \frac{21}{40} - \frac{3}{5} \\ = \frac{ - 2}{56} + \frac{21}{40} - \frac{3}{5} \\ = \frac{ - 10}{280} + \frac{147}{280} - \frac{3}{5} \\ = \frac{137}{280} - \frac{3}{5} \\ = \frac{137 - 168}{280} = \frac{ - 31}{280}$