tolong donk plizzz ya pakai cara nya

100/412:8/10x2,5=800/4120=80/412x2,5 jadi jwabannya .......

[tex]1)4.12 \div 0.8 \times 2 \ \frac{1}{2} \\ = \frac{412}{100} \div \frac{8}{10} \times \frac{5}{2} \\ = \frac{412}{100} \times \frac{10}{8} \times \frac{5}{2} \\ = \frac{103}{20} \times \frac{5}{2} \\ = \frac{103}{8} \\ = 12 \ \frac{7}{8} \\ 2)1 \ \frac{3}{5} \times 1 \ \frac{1}{2} \div \frac{2}{10} \\ = \frac{8}{5} \times \frac{3}{2} \div \frac{2}{10} \\ = \frac{8}{5} \times \frac{3}{2} \times \frac{10}{2} \\ = \frac{240}{20} \\ = 12[/tex]