Răspuns:
- [tex]a)28[/tex]
- [tex]b) \frac{12}{5} [/tex]
Explicație pas cu pas:
[tex]a) \: 3 \frac{1}{5} \times 8 \frac{3}{4} = \frac{3 \times 5 + 1}{5} \times \frac{8 \times 4 + 3}{4} [/tex]
[tex] \frac{15 + 1}{5} \times \frac{32 + 3}{4} = \frac{16}{5} \times \frac{35}{4 } \\ = 4 \times 7 \\ = 28[/tex]
[tex]b) \: 1 \frac{2}{7} \times 1 \frac{13}{15} = \frac{1 \times 7 + 2}{7} \times \frac{1 \times 15 + 13}{15} [/tex]
[tex] \frac{7 + 2}{7} \times \frac{15 + 13}{15} = \frac{9}{7} \times \frac{28}{15} \\ = 3 \times \frac{4}{5} \\ = \frac{12}{5} [/tex]
