a) (4-1¼:1⁹₁₆)x(-15⁵₈)= (4-⁵₄x¹⁶₂₅)x(-120/8)= (4-4/5)x(-15)= 1/5x(-15)=-3 b) 4/5-(1,2x5/12-0,8):(-1/8)= 4/5-(12/10x5/12-8/10)x(-8)= 4/5-(5/10-8/10)x(-8)= 4/5-(-3/8)x(-8)= 4/5-3=-2i1/5 c) [2i2/3-25:12,5]/(9-6x1i1/6)x(-2)= [8/3-2]/(9-7]x(-2)= [2/3]/-4= 2/3x(-1/4)=-1/6 d) [4/5x1i2/3-3,75]/5/9-10/27:(-5/6)= [4/5x5/3-3i3/4]/5/9-10/27x(-6/5)= [4/3-3i3/4]/5/9+4/9= [16/12-45/12]/1= 29/12x1=2i5/12
5. a) (4 - 5/4 × 16/25) × (-125/8) = (4- 4/5) × (-125/8) = 3i1/5 × (-125/8) = 16/5 × (-125/8) = -50 b) 2i2/3 - 2 2/3 2/3 2/3 ______________ = ___________= ___________= _____= 2/3 × (-1/4)=-1/6 (9-6 × 7/6) × (-2) (9-7) × (-2) 2× (-2) -4 c) 4/5 - (12/10 × 5/12 - 0,8) ÷ (-1/8) = 4/5 - (0,5 - 0,8) ÷ (-1/8) = 4/5 - 0,3 ÷ (-1/8) = 4/5 - 3/10 × (-8/1) = 4/5 - 12/5 = -8/5 = -1i3/5 d) 45/10 × 5/3 - 3,75 7,5 - 3,75 3,75 __________________= _____________= _____= 3,75 5/9 - 10/27 × (-6/5) 5/9 + 12/27 27/27 6. -3/4 ÷ 2 = -3/8 -8 + (-3/8) = -8 - 3/8 = -8i3/8 7. -3,6 × (-1,7) = 6,12 13,5 - 6,12 - 7,38 8. 1i3/5 + 1i2/3 = 8/5 + 5/3 = 8/15 + 25/15 = 33/15 = 2i1/5 -4 - (-1i2/3) = -4 + 1i2/3 = -2i1/3 2i1/5 ÷ (-21/3) = 11/5 × (-3/7) = -33/35 9. -4,8 ÷ (-2) = 2,4 -1/2 × 4/5 = -2/5 2,4 + (-2,5) = 2,4 - 0,4 = 2
