7.
[tex]1)\\a = 16\\\\\frac{3}{4}\cdot a = \frac{3}{4}\cdot16 = 3\cdot4 = \boxed{12}[/tex]
[tex]2)\\a = \frac{8}{7}\\\\\frac{3}{4}\cdot a =\frac{3}{4}\cdot\frac{8}{7} = \frac{3\cdot2}{7} = \boxed{\frac{6}{7}}[/tex]
[tex]3)\\a = \frac{10}{21}\\\\\frac{3}{4}\cdot a = \frac{3}{4}\cdot\frac{10}{21} =\frac{1}{2}\cdot\frac{5}{7} =\boxed{ \frac{5}{14}}[/tex]
[tex]4)\\a = 2\frac{1}{6}\\\\\frac{3}{4}\cdot a=\frac{3}{4}\cdot2\frac{1}{6} = \frac{3}{4}\cdot\frac{13}{6}=\frac{1}{2}\cdot\frac{13}{4} =\boxed{ \frac{13}{8}}[/tex]
[tex]5)\\a = 6\frac{2}{3}\\\\\frac{3}{4}\cdot a = \frac{3}{4}\cdot6\frac{2}{3} = \frac{3}{4}\cdot\frac{20}{3}=\frac{20}{4} = \boxed{5}[/tex]
[tex]6)\\\frac{3}{4}\cdot a = \frac{3}{4} \ \ \ |\cdot\frac{4}{3}\\\\\boxed{a = 1}[/tex]
[tex]7)\\\frac{3}{4}\cdot a = \frac{3}{28} \ \ \ |\cdot \frac{4}{3}\\\\\boxed{a = \frac{1}{7}}[/tex]
[tex]8)\\\frac{3}{4}\cdot a = 1 \ \ \ |\cdot\frac{4}{3}\\\\\boxed{a = \frac{4}{3}}[/tex]
a | 16 | ⁸/₇ | ¹⁰/₂₁ | 2¹/₆ | 6²/₃ | 1 | ¹/₇ | ⁴/₃
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³/₄ · a | 12 | ⁶/₇ | ⁵/₁₄ | ¹³/₈ | 5 | ³/₄ | ³/₂₈ | 1
