Answer:
Sum:
[tex] = \frac{3}{4} + \frac{9}{10} \\ \\ = \frac{30 + 36}{40} = \frac{66}{40} \\ \\ sum = \frac{33}{20} [/tex]
Product:
[tex] = \frac{33}{20} \times - \frac{5}{4} \\ \\ = - \frac{33 \times 5}{20 \times 4} \\ \\ = - \frac{165}{80} \\ \\ { \boxed{ \boxed{product = -\frac{33}{16} = -2 \frac{1}{16} }}}[/tex]
