Respuesta:
a) [tex]1 \frac{1 }{3} \div \frac {3 }{4} = \frac {1 \div 1\cdot3 }{3} \div \frac{3 }{4} = \frac {4 }{3} \div \frac{3 }{4} = \frac {4 }{3} \cdot\frac { 4 }{3} = \frac{ 4\cdot4 }{3\cdot3} =\frac { 16 }{9}[/tex]
b) [tex]2\:\frac{1}{5}\:-\:1.125\:-\:1\:\frac{2}{5}\:-\:2=-\frac{7}{5}+\frac{11}{5}-1.125-2=0.8-3.125=-2.325[/tex]
