Ответ:

Пошаговое объяснение:

3 2/7*2.8=23/7*28/10=92/10=9.2

7.2:2 4/7=72/10*7/18=28/10=2.8

9.2-2.79=6.41

6.41+2.8=9.21

9.21+2.79=12

0.9:12=9/10*1/12=3/40=0.075

84.24:1.2=70.2

85.24-70.2=15.04

2.4*15.04=36.096

15.04*2.5=37.6

37.6-36.096=1.504

0.047*16.9-0.9*0.047=0.047*(16.9-0.9)=0.047*16=0.752

1.504:0.752=2