Odpowiedź:
[tex]a) \: 2 \frac{1}{2} - 1 \frac{3}{4} = \frac{5}{2} - \frac{7}{4} = \frac{10}{4} - \frac{7}{4} = \frac{3}{4} [/tex]
[tex]b) \: 2 \frac{1}{2} \div 1 \frac{3}{4 } = \frac{5}{2} \div \frac{7}{4} = \frac{5}{2} \times \frac{4}{7} = \frac{10}{7} = 1 \frac{3}{7} [/tex]
