11) 7/4 = x/2; 12) (x+3)/12 = 4/3; 13) 7x = x + 25; 14) 0,4x - 6 = 0,6x - 9; 15) 3x + 16 = 9 - 10x; 16) 0,6(x + 1 1/3) = -1,2; 17) -3,4(x + 9 3/11) = -68; 18) x/3 + x/4 = -21; 19) 2m/3 - 4m/5 = 3; 20) 4a/9 - 1 = 5a/12

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11) 7/4 = x/2; 12) (x+3)/12 = 4/3; 13) 7x = x + 25; 14) 0,4x - 6 = 0,6x - 9; 15) 3x + 16 = 9 - 10x; 16) 0,6(x + 1 1/3) = -1,2; 17) -3,4(x + 9 3/11) = -68; 18) x/3 + x/4 = -21; 19) 2m/3 - 4m/5 = 3; 20) 4a/9 - 1 = 5a/12

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11) $\frac{7}{4} = \frac{x}{2}$ $4x = 14$ $x = 3.5$ 12) $\frac{x+3}{12} = \frac{4}{3}$ $3(x+3) = 48$ $3x + 9 = 48$ $3x = 39$ $x = 13$ 13) $7x = x + 25$ $6x = 25$ $x = \frac{25}{6} \approx 4.167$ 14) $0.4x - 6 = 0.6x - 9$ $0.4x - 0.6x = -9 + 6$ $-0.2x = -3$ $x = 15$ 15) $3x + 16 = 9 - 10x$ $13x = -7$ $x = -\frac{7}{13}$ 16) $0.6(x + \frac{4}{3}) = -1.2$ $0.6x + 0.6 \cdot \frac{4}{3} = -1.2$ $0.6x + 0.8 = -1.2$ $0.6x = -2$ $x = -\frac{20}{6} = -\frac{10}{3} = -3\frac{1}{3}$ 17) $-3.4(x + 9\frac{3}{11}) = -68$ $x + \frac{102}{11} = \frac{68}{3.4}$ $x + \frac{102}{11} = 20$ $x = 20 - \frac{102}{11} = \frac{220 - 102}{11} = \frac{118}{11} = 10\frac{8}{11}$ 18) $\frac{x}{3} + \frac{x}{4} = -21$ Multiply by 12: $4x + 3x = -252$ $7x = -252$ $x = -36$ 19) $\frac{2m}{3} - \frac{4m}{5} = 3$ Multiply by 15: $10m - 12m = 45$ $-2m = 45$ $m = -22.5$ 20) $\frac{4a}{9} - 1 = \frac{5a}{12}$ Multiply by 36: $16a - 36 = 15a$ $a = 36$

11) 7/4 = x/2; 12) (x+3)/12 = 4/3; 13) 7x = x + 25; 14) 0,4x - 6 = 0,6x - 9; 15) 3x + 16 = 9 - 10x; 16) 0,6(x + 1 1/3) = -1,2; 17) -3,4(x + 9 3/11) = -68; 18) x/3 + x/4 = -21; 19) 2m/3 - 4m/5 = 3; 20) 4a/9 - 1 = 5a/12

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