Question

помoгите... дам 20 баллов

Answer 1

а)

$\frac{7y}{12} = \frac{5}{4}\\ 28y=60\\y=\frac{15}{7}$

б)

$\frac{46}{15} -\frac{29a}{15} =\frac{1}{6}\\ \frac{46-29a}{15}=\frac{1}{6} \\ 6(46-29a)=15\\276-174a=15\\a=\frac{261}{174}\\a=1.5 (a=1\frac{1}{2} )$

в)

$(\frac{7}{18} +\frac{5z}{24} )*\frac{9}{11} =\frac{1}{3}\\ \frac{7}{22} +\frac{15z}{88} =\frac{1}{3} \\\frac{15z}{88} =\frac{1}{22}\\ 330z=88\\z=\frac{44}{165}$

г)

$x(\frac{4}{7} +\frac{5}{14} -\frac{10}{21} )=\frac{1}{4} \\x(\frac{24+15-20}{42} )=\frac{1}{4} \\\frac{19x}{42}=\frac{1}{4}  \\76x=42\\x=\frac{21}{38}$

д)

$m-\frac{5}{12}m=\frac{1}{4} \\ \frac{7m}{12} =\frac{1}{4} \\28m=12\\m=\frac{3}{7}$