1)
[tex] \frac{7}{5} - 0.(4) \times 2 {}^{ - 1} = \frac{7}{5} - \frac{4}{9} \times ( - 2) = \frac{7}{5} - \frac{ - 8}{9} = \frac{7}{5} + \frac{8}{9} = \frac{63}{45} + \frac{40}{45} = \frac{103}{45} [/tex]
2)
[tex]4 \div (2.7 - 1.38) {}^{2} = 4 \div (1.32) {}^{2} = 4 \div 1.7424 = \frac{4}{1.7424} = \frac{4}{ \frac{17424}{10000} } = \frac{4}{ \frac{1089}{625} } = 4 \times \frac{625}{1089} = \frac{2500}{1089} [/tex]
3)
[tex]5 + 3 \times ( - \frac{1}{4} ) = 5 - \frac{3}{4} = \frac{20}{4} - \frac{3}{4} = \frac{17}{4} [/tex]
