a) 3/4 + 2/3(- 8/12 + 1/4) = 3/4 + 2/3(- 8/12 + 3/12) = 3/4 + 2/3 * (- 5/12) = = 3/4 - 2/3 * 5/12 = 3/4 - 10/36 = 27/36 - 10/36 = 17/36 b) [(- 2/3)² : 8/9]⁻¹ = (4/9 * 9/8)⁻¹ = (4/8)⁻¹ = (1/2)⁻¹ = 2 c) √(25 - 19) = √6 d) (4⁶ * 8⁴)/16⁶ = 4⁶ * 8⁴/(4²)⁶ = 4⁶ * 8⁴/4¹² = 8⁴/4⁶ = (2³)⁴/(2²)⁶ = 2¹²/2¹² = 1 e) (√32 + 2√72)/4√2 = (√(16 * 2) + 2√(36 * 2)/4√2 = (4√2 + 6√2)/4√2 = = 10√2/4√2 = 2,5√2 f) (- 1,2)⁻² * (0,8)⁰ = (- 12/10)⁻² * 1 = (- 10/12)² = - 100/144 = - 50/72 = - 25/36 zad 2 18% = 18/100 = 0,18 12600 * 0,18 = 2268 laptopów popsutych wyprodukowano zad 3 600 zł ----- 100% 480 zł ------ x% x% = 480 * 100/600 = 48000/600 = 80% ceny pierwotnej kosztuje rower 100% - 80% = 20% zmniejszyła się cena roweru zad 4 x - wysokość drzewa 150 cm/120 cm = x/8 m = x/800 cm x = 150 * 800/120 = 12000/120 = 1000 cm = 10 m
