1) $$2 - \frac{3}{5} = \frac{10}{5} - \frac{3}{5} = \frac{7}{5} = 1.4$$
2) $$3 - \frac{12}{15} = \frac{45}{15} - \frac{12}{15} = \frac{33}{15} = \frac{11}{5} = 2.2$$
3) $$4 - 2\frac{1}{4} = 4 - \frac{9}{4} = \frac{16}{4} - \frac{9}{4} = \frac{7}{4} = 1.75$$