Как решить ?(дроби)(1/15 + 1/10 +12 .2/15 ): 1/15 = ?(2/5 - 3/10 + 1/20) : 1 .2/3 - 3/4 =?(1 - 2/3) : 2/3 +(4/5 -1) x 5 =?(7/8 - 1/2 ): 3/4 -5 : (1/3 -1/8 ) =? 

[latex] ( \frac{2}{5} - \frac{3}{10} + \frac{1}{20} ): \frac{1.2}{3} - \frac{3}{4} =[/latex]             [latex]1) \frac{2}{5} - \frac{3}{10} = \frac{4-3}{10}= \frac{1}{10} , 2) \frac{1}{10} + \frac{1}{20} = \frac{2+1}{20} = \frac{3}{20} 3) 1,2/3=0,4= \frac{4}{10} = \frac{2}{5} 4) \frac{3}{20} : 0,4= \frac{3}{20} : \frac{2}{5} = \frac{3}{20} * \frac{5}{2} = \frac{3*1}{4*2} = \frac{3}{8} 5) \frac{3}{8} - \frac{3}{4} = \frac{3-6}{8} = \frac{-3}{8} [/latex]