Question

Calculati: (1-0,4:0,8+3:1,2:[(2,6-7/3×42/49)×10/7]+{[4:(2-0,4)+1]:[7-2:(1-2/3)]}

Answer 1

(1-0,4:0,8+3:1,2:[(2,6-7/3×42/49)×10/7]+{[4:(2-0,4)+1]:[7-2:(1-2/3)]}=

1-0,5+2,5:[(2,6-2)×10/7]+[(4:1,6+1):(7-2:1/3)]=

0,5+2,5:(0,6×10/7)+[(2,5:(7-6)]=

0,5+2,5: 6/7 + 2,5=

3+25/10×7/6=

3+175/60=

(180+175)/60= 355/60=71/12