[tex]42:1 \frac{3}{4} -15,6+1 \frac{2}{3} [/tex]

42×3/4-15.6+2/321×3/2-15.6+2/321×3/2-15.6+2/363/2-15.6+2/363/2-156/10+2/35×63-2×78/10+2/3315-2×78/10+2/3315-156/10+2/3159/10+2/33×159+10×2/30477+10×2/30477+20/30=497/3016×17/30