Szczegółowe wyjaśnienie:
[tex]7 \frac{1}{3} + 6.6 =7 \frac{1}{3} + 6 \frac{6}{10} = 7 \frac{1}{3} + 6 \frac{3}{5} = \frac{22}{3} + \frac{33}{5} = \frac{22 \times 5}{3 \times 5} + \frac{33 \times 3}{5 \times 3} = \frac{110}{15} + \frac{99}{15} = \frac{209}{15} = 13 \frac{1}{15} [/tex]
[tex]7 \frac{1}{3} + 6.6 =7 \frac{1}{3} + 6 \frac{6}{10} = 7 \frac{1}{3} + 6 \frac{3}{5} = \frac{22}{3} + \frac{33}{5} = \frac{22 \times 5}{3 \times 5} + \frac{33 \times 3}{5 \times 3} = \frac{110}{15} + \frac{99}{15} = \frac{209}{15} = 13 \frac{1}{15} [/tex]
[tex]4.2 + 3 \frac{1}{8} = 4.2 + 3.125 = 7.325 = 7 \frac{325}{1000} = 7 \frac{13}{40}[/tex]
[tex]13.8 - 3 \frac{3}{4} = 13.8 - 3.75 = 10.05[/tex]
[tex]1 \frac{1}{7} + 5.5 = 1 \frac{1}{7} + 5 \frac{1}{2} = \frac{8}{7} + \frac{11}{2} = \frac{16}{14} + \frac{77}{14} = \frac{97}{14} = 6 \frac{13}{14} [/tex]
[tex] \frac{1}{2} \times 4.2 = 0.5 \times 4.2 = 2.1[/tex]
[tex]3.6 \times \frac{3}{4} = 3.6 \times 0.75 = 2.7[/tex]
[tex]12.4 \div \frac{1}{3} = 12 \frac{2}{5} \times 3 = \frac{62}{5} \times \frac{3}{1} = \frac{310}{5} = 62[/tex]
[tex]5 \frac{1}{4} \div 2 \frac{2}{5} = \frac{21}{4} \times \frac{5}{12} = \frac{105}{48} = 2 \frac{9}{48} [/tex]