[tex]a)6 \frac{5}{8}= \frac{6*8+5}{8}= \frac{53}{8} \\ \\ 1 \frac{7}{12}= \frac{1*12+7}{12}= \frac{19}{12} \\ \\ \frac{53}{8} + \frac{19}{12}= \frac{53*12+19*8}{96}= \frac{636+152}{96} \\ \\ = \frac{788}{96}= \frac{394}{48}= \frac{197}{24} [/tex]
b)
[tex]- \frac{11}{12}+ \frac{7}{8}= \frac{-11*8+7*12}{8*12} = \frac{84-88}{96}= -\frac{4}{96}= - \frac{1}{24} [/tex]
c)
[tex]- \frac{5}{16}* \frac{8}{25}=- \frac{1}{10} [/tex]
d)
[tex] \frac{\frac{5}{7} }{ 1\frac{1}{14} }[/tex]
[tex]1 \frac{1}{14}= \frac{1*14+1}{14}= \frac{15}{14} \\ \\ \frac{\frac{5}{7} }{ \frac{15}{14} }= \frac{5}{7}* \frac{14}{15}= \frac{2}{3} [/tex]
