Срочнооооооооо !!!!!! Только а) пжжжжжж

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$(3 \frac{7}{30} -1 \frac{5}{12} ):18 \frac{1}{16} = \frac{436}{4335} \\ \\ 1)~3 \frac{7}{30} -1 \frac{5}{12}= \frac{3*30+7}{30}- \frac{1*12+5}{12} = \frac{97}{30} -\frac{17}{12} = \frac{97*2}{30*2} -\frac{17*5}{12*5} = \frac{194}{60}-\frac{85}{60}= \\ =\frac{194-85}{60}=\frac{109}{60} \\ 2)~\frac{109}{60}:18 \frac{1}{16}=\frac{109}{60}: \frac{18*16+1}{16}=\frac{109}{60}: \frac{289}{16}=\frac{109}{15*4}* \frac{4*4}{289}= \frac{109}{15}* \frac{4}{289}= \\ = \frac{109*4}{15*289}= \frac{436}{4335}$