Răspuns :
[tex] \frac{2}{7} - ( - \frac{3}{4}) \times \frac{7}{8} = \frac{2}{7} - ( - \frac{3}{4} \times \frac{7}{8}) = \frac{2}{7} - ( - \frac{3 \times 7}{4 \times 8}) = \frac{2}{7} - ( - \frac{21}{32}) = \frac{2}{7} + \frac{21}{32} = \frac{211}{224} [/tex]
2 / 7 - ( - 3 / 4 ) × 7 / 8 =211 /224
= 2 / 7 + 21 / 32 = → cmmmc al numitorilor 7 si 32 este 7 x 32 = 224
= ( 2 × 32 ) / 224 + ( 21 × 7) / 224 =
= ( 64 + 147 ) / 224 =
= 211 / 224