(6 1/8 * 1 2/7 - 2 11/14 * 1 8/15) * 1 3/5=
= (49/8 * 9/7 - 39/14 * 23/15) * 8/5=
= ( 63/8 - 299/70) * 8/5 =
= (2205/280 - 1196/280) *8/5 =
= 1009/280 *8/5 = 1009/175 = 5 134/175
по действиям
1) 6 1/8 * 1 2/7 = 49/8 * 9/7 = (7*9)/(8*1) =63/8= 7 7/8
2) 2 11/14 * 1 8/15 = 39/14 * 23/15 =
=(13*23)/(14*5) = 299/70=4 19/70
3) 7 7/8 - 4 19/70 = 63/8 - 299/70 =
=2205/280 - 1196/280 = 1009/280= 3 169/280
4) 3 169/280 * 1 3/5 = 1009/280 * 8/5=
=(1009*1) / (35*5) = 1009/175 = 5 134/175