0,2⋅(-3/11)⋅5⋅11/15 = 1/5⋅(-3/11)⋅5⋅11/15 = -(1⋅3⋅5⋅11)/(5⋅11⋅15) = -3/15 = -1/5 = -0,2
5/18⋅(-5,34)+5/18⋅(-4,63) = 5/18⋅(-5,34-4,63) = 5/18⋅(-9,97) = - (5⋅9,97)/18 = - 49,85/18 ≈ -2,769
0,21·2,3 = 0,483
15,6:8 = 1,95
8 3/4⋅1 3/14 = 35/4 ⋅ 17/14 = (35⋅17)/(4⋅14) = (5⋅17)/(4⋅2) = 85/8 = 10 5/8 = 10,625
4 2/15+4 3/16 = 4 + 2/15 + 4 + 3/16 = 8 + 2/15 + 3/16 = 8 + (2⋅16 + 3⋅15)/(15⋅16) = 8 + (32 + 45)/240 = 8 + 77/240 = 8 77/240 = 8,3208(3)