3m + 2m + 4m = m * (3 + 2 + 4) = 9m

$\frac{1}{2}a + \frac{1}{3}a - \frac{1}{6}a = a * (\frac{1}{2} + \frac{1}{3} - \frac{1}{6}) = a * (\frac{3}{6} + \frac{2}{6} - \frac{1}{6}) = \frac{4}{6}a = \frac{2}{3}a$

0,9b − 1,3b + 0,7b = 0,3b

x − 0,2x − 0,7x = 0,1x

$\frac{1}{12}m - \frac{1}{4}m - \frac{1}{3}m = \frac{1}{12}m - \frac{3}{12}m - \frac{4}{12}m = -\frac{6}{12}m = -\frac{1}{12}m$

$с - 0,8c - \frac{1}{5}c - \frac{1}{2}c = с - 0,8c - 0,2c - 0,5c = -0,5c$

0,3a − 0,2a − 0,7a + 0,2a = a * (0,3 − 0,2 − 0,7 + 0,2) = −0,4a

4a − 6a − 2a + 12 − 11 = a * (4 − 6 + 2) + 1 = −4a + 1

$\frac{2}{3}a + \frac{3}{8}b - \frac{1}{6}a - \frac{1}{4}b = \frac{4}{6}a + \frac{3}{8}b - \frac{1}{6}a - \frac{2}{8}b = \frac{3}{6}a + \frac{1}{8}b = \frac{1}{2}a + \frac{1}{8}b$

$\frac{5}{7}k - \frac{2}{3} - \frac{3}{14}k - \frac{1}{3} = \frac{10}{14}k - \frac{2}{3} - \frac{3}{14}k - \frac{1}{3} = \frac{7}{14}k - 1 = \frac{1}{2}k - 1$

$0,2m - \frac{2}{9} - 4m + \frac{5}{9} = -3,8m + \frac{3}{9} = -3,8m + \frac{1}{3}$

$\frac{1}{2}a + \frac{1}{3}c - \frac{1}{2}a + \frac{2}{3}c = 0 + \frac{3}{3}c = c$